I wrapped the harness up with nylon tape to clean it up. I think it turned out great. I can finally get back to finishing this thing up. I ran in to a bit of a problem with the fuel pump relay circuit. The relay was clicking on and off randomly. It was really strange. I checked my wiring all the way back to the ECM and found no problems. The ECM was commanding the relay correctly. I thought that I may be a bum ECM. I did some digging and found a thread from 2014sierraAT (
Thread Link) and he was having a similar issue. I too have the Dakota Digital BIM module so I enabled boost and it started working correctly. I called Dakota and they told me to disable boost and gear indicator. So a little conflicting information, but it seems to be working now. It has a lifetime warranty so if it kicks the bucket, they will send another one. Part of hot rodding.
I'm still having a strange problem with the throttle pedal. My engine is from a Denali. It had the adjustable pedals. I switched out to a non adjustable pedal. Come to find out, the non adjustable has twice the travel of the adjustable. So I am getting 100% throttle half way through the pedal travel. There are 2 TAC module part numbers for 2003, so I am going to try the other to see if it helps.