I've replaced the alternator and the battery on this vehicle, but sometimes the Volts light comes on and the headlights flicker. Is there any wire/wires I should look at? It will do this for a few minutes, stop, and then do it again.

Also....

I put new plugs on the car, but the plug wires are a real pain. The distributor is in a hard to reach location. It is located near the back of the engine and underneath. I've never seen on in such a difficult place. Do I need to put the car on a lift and get a the distributor from underneath?