Please help! I'm having a Meltdown!

What I did notice on the alternator field connections when the car stalled was that both connections were loose and the one insulator was brittle and when I tightened it just cracked and fell apart. I am going to try with new insulator washers and see what happens.

After changing the insulators and before connecting wires to terminals, an Ohm meter could be used to verify the terminals are isolated from ground. Meters do this better, than visual inspection.