No need to replace the factory wires. Lakevillessei recommended that I use coke on 'em too. Try that too. Just make sure you don't have any corrosion on the cables, or the main battery bolts. ALWAYS use dielectric grease on stuff like that. I've got a big can of that, just for the occasion. Not sure if it is necessary, but I put it on the battery cables, starter connections, ICM connector, both alternator connectors, and injector connectors [those are a PITA to get off.. just leave those]. Basically, the main stuff required for the car to run. Just in case ya know.. I'd be pretty pissed if a little bit of green crud made me pay $50 for a tow home.
'89 SSE - GX3 -190k, 155k on body - Back for another ride.