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Hey all, first post and hoping this can help out. As many of you know and or finding out, the 24's and up are apparently a new style Firewall Grommet system leading into the truck from behind the battery. But not to worry, this will hopefully be the clearest new how to so far without a youtuber making a video of this. The truck now, instead of having a nipple coming from the firewall grommet on the engine bay side, is now a plastic bezel. The nipple can be located from under the dash still, however, and is still just as easy as an install as before. Pic 1 is from the engine bay. You can see the channel where the wire will exit/enter the truck. Pic 2 is from inside the truck and what is looks like if you peel the grommet back, which does not need to be done because then you'll need to replace the rubber around the grommet to around the plastic shroud which is not the easiest thing to do. Just use an exacto #1 and cut a plus from the inside of the truck in the nipple. Pic one shows where the wire will exit. Pic 3 shows a 4ga wire in it. It fits 4ga wire really well. No sure about 2 or 0... you may have to trim the nipple off then just make the plus/X cut bigger. I also did not need to remove the battery to do any of this. Just work from mid engine with a ladder/step stool. Not the side of the truck. Step 1. Take out the multifunction power supply converter box and bracket that is located behind the glove box and bolted to the kick panel right underneath the firewall grommet. The two tabs holding this box in need to be pulled towards you (the rear of the truck) and slid up. They will be blocked by the A/C fan I believe it is, but nevertheless cannot be pulled all the way up enough. Carefully pull it out. You'll have to finagle it a bit, but the box will come out. This is the only way to access the second 10mm nut that's on the stud holding the bracket in place. You do not need to remove the wire harness. I didn't. Remove both 10mm nuts with an extended socket. Step 2. I used an exacto like #1 blade and sliced a plus sign in the power wire pass through nipple. Step 3. Electrical tape a long zip tie to the wire. Use a little soapy water or some lubricant (I used just a little petroleum jelly) to slide the power wire through the hole. I went from the inside of the truck and pushed it to the outside (inside the engine bay). Continue install as you would with all the other older amp/power wire install guides out there. ...Special Notes... You may need to remove the plastic cover kickplate that is plastic welded to the floorboard part of the carpet placeholder cover. I did this by removing the fuse box cover plate then removing the 8mm screws. This allows you to pull the panel backwards and pop out the kickplate. The floorboard part must be pulled upwards. Do not try to separate these two pieces at the seam! They are plastic welded together. For another good run through check out here: https://www.trailboss.org/threads/firewall-grommet-change-in-the-2024-lt-trail-boss-for-power-wire.2109/ Hope my photos are more helpful.