Door wiring

If you mean the side mirrors they have the base mirrors, then basic power mirrors, then heated mirrors and electrochromic mirrors. Then there are auto folding mirrors, turn signal repeaters and puddle lights that were options on those trucks in various versions. They use the same harness for all of the trucks from the base up to the fully loaded ones so you may have connectors that do nothing even though they are there. In this case I cannot see the images because of a fault in the site so cannot tell you exactly what the plug does and you probably won't see the ones I posted that are for your truck, if you tell me the wire colors and the color of the plug I might be able to find it if I look at the other versions of that truck, like the higher optioned GMCs or Cadillac's.

The colors sound like the ones used on the optional mirrors that have the indicators and puddle lights. Blue is commonly turn signal, white is common for brake lights Orange with and without a trace is usually battery power and Black w or w/o a trace is ground.
I'll have to look at the Cadillac wiring on the GM system when it comes back up and see if they are shown on there.

OK now that the images are back I can dig some more, what is it plugged into? I see two connectors in some of the diagrams but the wire colors don't match up, however in those it looked like they had the power folding and telescoping mirrors as well a as heated and electrochromic mirrors. I doubt those items can be added even with a module change as they would still need the Caddy BCM and option codes. The BCM isn't going to work in the Chevy because of the VIN mismatch.