Is there a schematic out there for doing the harness changes when a J-Spec engine is dropped into a NA S5. I bought my 90 T2 and the fine folks I got it from put a Jspec motor into it, but I'm not all that confident that they wired up everything correctly. It looks like they used the original harness and tried to change pins. I make that assumption based on the fact that several of the engine connectors are missing and the wires are just plugged in with the blade connectors

 

Buy a USDM harness. Check ebay, they go for about 100-125$.

 

Harness will run the car with no modifcation but you will need to cut open your old harness to remove the wiper harness and you will need to add a wire so that your temperature gauge will work.

 

not for an S5

 

Yep. S5 jspec emissions harness and jspec ecu plug right into an S5 NA car fine - except for the wiper and temperature gauge.

Don't do it though. It would be WAY easier to just use your NA harness.