HAd one with a bad connection pump out over 100 volts.
Fried the big wire under the dash. Was over 1 inch of it missing, and about 2 inches of insulation on each side burned away.

Put in a 100 amp alt and converted to the newer style voltage reg, but the guy that put in the wiring, had a bad connector so it dropped contact.

Prior to that happening, it swelled and boiled out 3 batteries.