long story short:

heads/cam LS1/TH400 from '00 Camaro being put in a 2003 silverado that was originally a 4.3/auto truck....got a blue/green connector V8 truck harness that i was told was from a 2003 but the wiring in the C2 fuse block connector more closely matches a 2005...problem i have is in that C2 connector, pins A8, D5, and F10 are empty....not cut or removed, just weren't ever there. For some reason, i cannot find a diagram for a '03 4.3 silverado engine harness to see if that matters. the 3 missing wires are 2 battery(+) and one ignition voltage wire in the V8 harness but i dont know where they went to or what the corresponding pins in the 4.3 fuse box are.

I know for a typical 4.3 to 5.3 swap, you just get the matching year V8 harness and its plug-n-play. The LS1 isn't anything different, just a few different locations on some sensors but the harness & ecm don't know the difference once it's all plugged in. that's my main question i suppose, is what i have plug and play or do i need to repin the fuse block connector?

I already have added the appropriate pins and pigtails for the drive by cable throttle body and i do the tuning myself as well, i'm only concerned with the wiring at this point.

Thanks.