I have a wiring diagram, and have new wiring harness, but struggling with the orientation, routing of the wires. My harness has a split close to the alt wires and needs to fold back to run to starter, ,but wires seem to short to reach. Has to be something I'm doing wrong. Maybe the harness runs in front of engine??
The wires run on top of the engine, nestled between the intake and the valve cover. Usually, there is a guide/retainer there that the PVC hose snaps into. Then, the alternator and coil wires are good. The oil pressure wire drops down and the starter wires run down behind the alternator bracket and under the engine below the manifold/header under the motor mount. Here's mine. The factory wires are under the MSD wire loom that is on top, next to the PVC hose.
Look around on here, Page 12-14 for example: http://www.buick-riviera.com/servicemanual/120-93-153.pdf The V8's pretty much follow the same path
