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It was suggested that I place the write up on the custom gauge installation in this section so I will do just that. A bit of background: this truck is brand new with just under 8000 km on the clock. It has already seen -45C and some off road conditions. I am a business owner (Arrowsmith Project Management Limited) and this is one of my trucks.


First: a special thanks to everyone who has discussed the upfitter switches using the GM parts. I was very excited about that and was going to go that way but with discussions at the local parts counter about being my responsibility and that it would void the warranty and such I decided to do my own thing as all of this 12V stuff just needs a source and a ground. No ECM or other modules to plug into etc.


Second, because I bounce down roads everything has to be solid, secure and of industrial grade to not fall apart in the middle of nowhere.


Here is the installation process.


FYI get the right tools - in this case the trim removal tools or you could end up with scratches and nicks like this. (PIC 1)


PIC 2 and 3 - OEM trim of the AT4 before


PIC 4 and 5 - Pay close attention to how things come apart - watch all the videos and read all the existing write ups on removal of panels. This TAKES TIME. Go slow and be patient. There are 2 clips that will break if your removal of the console lower trim piece on either side is removed in haste. 


PIC 6, 7 and 8 - The removal process.


PIC 9, 10, 11 and 12 - Switch locations and layout - plan this out carefully. measure as many times as you need to. Take lots of pictures. I opted to use the OEM location as best I could for 2 switches. These ones control my front light bar from Bright Source and Strands. It has a main ON/OFF and a secondary driving light in both amber and white. This resulted in first installing a SPST rocker and a SPST moment switch. The moment was later swapped out for a SPDT rocker. I had a little trimming to do under the knee bolster panel. 


PIC 13, 14 and 15 - Trimming the drivers side lower console panel - this was done to house the cluster of switches for all the other goodies I need. (Reverse Alarm (1), Buggy Whip (1), Overhead Rotating Beacon (2), winch (1) and rear facing service lights (1))



















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PIC 16, 17, 18 - Wires, wires and more wires. I used a lot of 14 ga wire. So far 22 wires came into the cab, noting that the winch and buggy whip wires are not yet installed. I tried to map everything, colour coding, labelling and building harnesses as best I could. 





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PIC 19, 20 and 21 - Loom, lots of it. Note that I will be installing some heat wrap on the ones that run above the block later today.




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    • By ArrowsmithPML
      With all the support there is with the upfitter switches, I thought I would give others another write up on a full custom switch (and light install). 
      If this is the right location for that I will add it tomorrow. 
      Please advise.
      So ive been seeing the conversion on 08-13 Sierras , and very popular on Silverados even the 14-16 conversions. On feb 1 some jack ass cut me off and hit my front bumper and fender , lucky for him i was already looking into doing a 2018 denali headlight conversion with the gen5 wiring harness and 2015 HD front bumper with 2500 all terrain grille To keep the theme going. As I researched could not find anything on the 2014-2018 sierras being converted to HD , all the guys i saw on IG with them had shops or buddys do them. Some guys welded either the 1500 or 2500 brackets lower ,enlogated the holes lower, redrilled , some had no gap -some liked oem gap between the grille/fenders. I did find two guys I kept intouch with they were a lot of help. One sent me pictures on how to re-drill the stock bumper brackets lower and cut some parts off it to clear the bumper , the other told me 1/2 above the existing holes . I took it upon myself to source a complete front bumper from ebay with everything $750 with shipping all i have to do is paint it , found a all terrain grille on ebay for $300 , had to buy the 2500 bumper guides and 2500 bumper fillers no luck on hood yet.while the parts arrived i bought the 2018 denali lights from fankie on here and the harness from gen5 easy bolt on by the way. When all the parts arrived i grabbed my grinder and drill .
      To start i took the 15torque head screws and 7mm from the sides of the wheel wells , took the 12 plastic clips from the upper cover , removed the 4 top 10mm bolts ,pulled off the bumper filler pieces between the grille and bumper , exposing the 10mm 4 bottom grille bolts , then removed the grille. Gaining access to the 4 18mm bolts that hold the bumper on the brackets, i loosened but did not remove till i went under the front bumper and removed the 2 outter 15mm bolts that hold the bottom of the bumper , i loosened the inner 15mm bolts but did not remove , once that was done i removed all 18mm bolts  holding the bumper and took it off . Once off the stock 1500 bumper brackets have 3 15mm bolts in a triangle pattern, i removed all 6 and removed the tow hooks , the tow hooks will be eliminated from this . Once i had the brackets off i measured 1/2 inch above each hole . Now this is important if you want oem gap like myself i drilled a hole slightly bigger than the bolt going threw at the center of that 1/2 mark . If you dont want gap id suggest drilling under the 1/2 mark and possibly enlongating that hole down wards for adjustment. By drilling the hole a 1/2 inch higher it drops the bracket to clear the 2500 grille . In addition to redrilling the bracket you have to cut an L shape on top right next to the top bolt that the bracket has , i actually cut the bottom of the bracket and eliminated the bottom slot for the second 18mm hole because i was having issues lining up , ended up not being the problem , i found that out of the 6 15mm bracket bolts you only use 4 the top and inside 15mm the outter 15mm that completes the triangle actually hits the hd front bumper and it sags in the back ,so removing levels the bumper flush , i tried grinding the head down and still no luck removing was the fix. With the bumper off , you want to remove the 1500 bumper guides 3(7mm) bolts rachet wrench works best and socket aswell , install the 2500 bumper guides with same bolts same place these support and clip on to the new 2500 bumper filler pieces under headlights which youll have to buy . They clip and slide right on , the two bottom outter 10mm bolts that held the old grille will hold these in place and the other two 10mm in the middle from the old grille will be eliminated. See pictures.To finish securing the bumper filler and guides you have to screw the  7mm and 15 torque screws by fender trim , you will either have to buy the 2500 or 18 fender trim pieces or just trim yours roughly enough to bolt on the remark to trim perfectly and level like i did cant even tell .So Once the guides and fillers are installed grab the redrilled bumper bracket to your liking in gap, make sure its clearanced with the L shape you can rebolt bolt to frame leaving the outter 15mm off at that point you can lay the new bumper on the brackets rebolt the top 18mm bolts the bottoms wont line up -i eliminated by grinding off ,see pic -you can reconnect the lower 15mm outter brace and tighten , youll find out that it bolts right up and if you drilled at 1/2 center like me you keep that stock oem gap maybe a bit tighter gap actually but it looks good , you can then install the grille by pushing the clips in and only bolting on the the top 4 10mm bolts once done youll find that the gap is nearly perfect if you drilled at center of the 1/2 mark , some drill under the 1/2 mark to get less gap and some enlongate the hole lower towards the original hole  to adjust and have no gap , but i see that as rubbing issues with paint.
      sorry for rambling on on the install , i will try to post all my pictures size will be limited and ill go back to proof read fix anything that i missed. Let me know waht you guys think or if you need help

    • By ArrowsmithPML
      Ok guys (and gals),
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