About engine wireing harness

[Minnesota cutty]

I know I got replace my engine wireing harness because of the problems I've had in my 79 cutlass Calais my question is what harness do I look for for my car cause I have chevy motor in mine its 73 chevy 350 motor when i go looking for it of parts cars to what ones will be the same to my bad harness in my car and cars and years can anyone help me out ????????I want get my cutlass alive again View attachment 1075

 

[Olds 307 and 403]

First thing is what gauges do you have? Was it a factory sbc car?