Me being the "I learn better by doing" kinda guy, I took out just about all of the wiring in my 89 RS. Only thing I left were the leads for the lights, fuel pump lead, and I think thats it. I didnt know alot about 12v systems, so I rewired the WHOLE car just for learnings sake. Fuel pump (well, safety switch), wired fans, completly rewired the fuse block (yes, its wired with the correct 12v leads, ie. constant, run, start/run). Im puttin in a carbd 383 so electronics are at a minimum.

I jsut have a few basic questions. First off, Im reusing my stock LO3 alternator. Its got 1 red wire (appx. 10ga) that I wired to the starter with a fusible link, and then its got a connector thats got another red wire (also appx. 10ga) and a tan/white wire. I took the red wire from the connector and just put a fusible link on it and ran it to the other main red wire on the alternator. But whats the deal with the tan/white wire? I heard somewhere that I just wire it to 12v ign source, only on with key in ON position. Is this right? Does it need 12v, or does it have to be 5v?

My other question is wiring a new distributor. Im getting an accel HEI unit from summit, non-cc. What wiring is involved here? Just a switched 12v power wire and a tach wire for the gauge?

Here is a quick drawing of my alternator wiring

 

IIRC, with the alternator, the tan/white needs to be hot only when the key is in the on position. This is the +12 volts that energizes the alternator. These wont self energize when it starts turning so they need that tan/white wire hooked up.

 

how about when I hook up my voltmeter gauge? what exactly is it reading, the battery or the alternator?

 

On my 88 the large wire on outside post of the altenator is connect directly to the battery positive cable (no fuseable link,) but the cable (which goes to the starter) has two quick-disconnects for the fan fuseable link, and an inline fuse for power distribution.
From the alternator 4-wire connector, the red wire has a fueable link to the starter, one brown(tan)/white wire to the fuse panel (hot at all times,) and one brown wire to the instrument panel for the voltage indicator.