Helping a friend, someone did a ls conversion on his cart but didn't finish it. 97 camaro with 99 ls motor. They switched the pcm harness and the headlight harness but didn't touch the dash harness. I'm trying to get the gauges to work. Any insight on were to begin or what I need will be greatly appreciated, Thanks.

 

Harness is also from the 99 if that makes a difference