I built a custom harness for a Duramax Colorado swap. It was an LB7 though.
The harness was VERY complicated and in-depth....I made it so it used the factory Colorado underhood fuse block (the Duramax ECM was hooked up to all of the proper "ECM, TCM" etc fuses in the Colorado fuse block...I made it so ABS was retained/working, factory colorado ignition switch, factory cruise control switch....even the factory Colorado instrument cluster (and all cruise control/change oil/etc warning lights) worked with the Duramax.
Ben
Humble brag
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