Well there is 2 plugs nere the battery on the harness that will need to be repined or cut the match the old harnesses plugs. And the MAF plug will need to get extended about 3 feet or so, and the power steering idle control plug that plugs into the bottom nere the rack.There is a brown 12 pin plug that comes out nere the ECU on the SR harness that will need to be repined to fit up to the brown plug up under the dash.that plug is for your tachometer signal,ignition start ,etc. And if you have a 89 -90 S13 the power steering resorvoir and power steering hard lines will need to be replaced with 91-94 resovoir and lines. But other than that its a straight foward swap. But if you run into any problems e mail me at
[email protected], my name is brian.