Wiring Harness Replacement and LQ4/4L80E/NP241C Swap Integration

[shep151]

I'm in the late stages of planning and beginning the electrical modifications for my swap. During its previous life, the wiring harness in my 1978 K10 was modified and cobbled together in such a manner it's pretty much unrecognizable in many places, so I'm replacing it with a Painless harness. I chose Painless because it's a bit cheaper than AAW, and it's less "finished". Since I'm going to be heavily modifying it, this suits my needs just fine. I'll be doing as much modification and harness integration as possible before installing, looking for as clean of install as possible.
I have the entire donor truck (2005 Silverado 2500HD), so I'll be retaining as much of the wiring harness and PCM functions from it as I feel is necessary. Some of the PCM and electrical functions I'll be retaining (and adding) are:
Cruise Control
Tow/Haul
DRLs
AC
Full donor Power Distribution Center
Electric Fans (With indications and manual control switches)
Avital 4105 Remote Start/Keyless Entry
Full LED swap
Dakota Digital RTX instrument cluster, with BIM-01-2 feed

My intention is that I'll update this thread as I complete portions of the process so that it'll be here for others who are doing something similar in the future. We'll see if I can keep to that...

 

[shep151]

Update:
Yeah, I'm not good at posting updates.
Plan changes:
Using the donor's power distribution center proved itself totally not worth the trouble, so that was abandoned. I did install a 6 relay/10 fuse distribution block on the driver's side wheel well.
The donor's wiring was pretty crispy, so I went with a BP Automotive stand alone harness. It's put together very well, and supports cruise control and AC.
The BIM-01-2 doesn't support multiple connections, meaning I can't have my BT scan dongle running and have the DD dashboard running at the same time, so I returned the BIM unit.

The Painless harness was PAINFUL. Since I was making modifications, I needed a full wiring schematic. Painless doesn't include this. They have a very detailed manual with small "system level" schematics, and I would recommend them for someone who is only replacing a stock harness, but I spent a LOT of time trying to figure out the exact source of power for some wires in the harness so I knew how to implement my mods.

Overall, it's going well. It's taking well over twice the time I expected (mostly wiring harness work) but such is life.
The engine has been installed. I'm finalizing the wiring harness installation. All that's left is to wire up the stereo head unit, brake switch and ashtray mounted switch panel for the main harness. The BP Automotive engine harness is almost completely installed, and the AC clutch relay control line needs finalized. I have all the pieces/parts from Cold Hose ready to make the AC hoses once the front end is rebuilt.

It's reaching the point where it's starting to look like things are speeding up.

 

[hoagster]

Keep posting, and don't forget to include photo's they are extremely helpful. I have found I didn't take enough photo's when I torn my truck down. And for those doing a motor swap sometimes what seems not important to you is extremely valuable to others that don't have your skills. Enjoy and welcome for Norcal!

 

[shep151]

The truck is finally in service! Still working some kinks out.
Today I finished the install of the Winters Sidewinder. It looks great next to the JB Fab cable transfer case shifter. It'll all look much better when I get to revamping the interior!