You've prolly seen the end of my project thread, but here's the basic problem as I've become able to see it. Anyway, started up it was obviously almost dead, got going and the light faded on, gained up some rpms, faded off, and so on and so forth, but every time I went low on rpms it would come on just a little bit, I guess because it wasn't charging so well. So dead battery, yeah? I need to go find a battery for my DMM now, but what should I be looking for in terms of readings?
With the car running, assuming your alternator is good, you should see around 13.8-15.5 volts. Assuming your battery is good, it should have about 12.5 volts with no load, and shouldn't drop below about 9 volts when cranking.
fluid leavle is checked by poping the caps off the battery, their should be some sort of little leavle notchs down in there thatyou fill till they are covered, if you don't see them then just fill it till the battery has 1/2 of water/acid past the top of the plates, your repair book tells you how to do this as well.
at idle your battery should be charging, 13.5 volts is pretty standard I think.