Starting to mod/upgrade my FY25 RST

cheapie408 · March 8, 2025

I went from a 19 LT 5.3 to a 25 RST 3.0 Duramax. This is my first brand new truck and first diesel vehicle so I hope to have it for some time. One thing I hate about these truck is 95% of them have black interior along with no interior mood lights which make it extremely dark inside. For the past 10+ years, all of my vehicles have some kind of interior ambient lights and I've gotten used to it. When I bought my X7 in 2019, what really got me was the interior ambient lighting. Traded it in recently and got the new X7 and I'm still enjoying the interior.

So onto the truck, I've only owned for a week, started to transfer the audio equipment from the old truck over and decided while I have the panel off, I decided to sound deaden the doors and add some lights. I spent a good 3 hours on the driver side doors and figuring out the routes to which it would give me the most factory look. I don't want what to do with the dash yet but I have a path forwards for all four doors.

I got an a symphony LED kit with 18 lights that would allow for lights in the door handle, door cup holder and a strip for each door plus footwell lightings. The kit comes with 1 master controller and 4 wireless slave so you don't need to route wires from the cabin to each door. I tapped into the constant 12V to the door switch. I figure when it's off, the draw would be so little that it's not going to drain. I can't find a switched 12v circuit in the door but if someone can point out which wire is a switched 12v I would much rather do that. I searched everywhere and found nothing on these lights install for our truck so I figure I'd document it here, maybe it can help someone.

Under the door handle, there's already an existing hole, the led just slide in there and I hot glue it to it. I had to drill a hole in the cup holder slide in the cap then also hot glue. The LD strip slide between the cracks of the door handle and carefully pushed into the crevices.

If you guys are interested, I can take detail photos of allt he penatration points as this was the longest to get figured out. For the remaining 3 doors, it should probably only take 30 minutes per panel at the most.

For the sound deadening, I added the buytle material plus a layer of the foam material on both the outer and inner shell where I could.