Just picked up my 2021 3500 Extended 15 passenger and I want to do some DC wiring for USB charging in each row.

The only real power related option the van has is the heavy duty tow package, so the trailer wiring is already used, and I don't want to tap into it.

Looking at the upfitter's diagram, I see some blunt cut wires in various places, but not sure if they are only there with certain packages. I can't find any under the instrument cluster, where a couple are listed.

Does anyone know if in this year, or other recent years there are any blunt cut wires available? Has anyone done any sort of DC wiring like this? I can't find anything in the forums. I did find an upfitters fuse block for up to 2020 model year but not sure if it will work, and hoping to avoid the firewall.

The basic concept is to have something like this in each row:


That would allow charging similar to our smaller van that only holds 5 of my 8 children. Something for everyone in each row (minus the ones with laptops...they can pay for their own, lol)

Bonus question: What size are the seat nuts? I tried 17mm, 19mm, 11/16 and 3/4 and none of them fit quite right...either too loose or too tight. I've never even seen an 18mm...but I guess I'll have to find a socket.