57 died again?

[la hi]

I installed the fuel tank and went for a ride. I hit it on a straight away and about 5 seconds later it died, no electricity, coasted into a business.
This is the second time this happened. The first time I melted the wires on the ign switch. This time the battery seams to be shorted out. sparks fly when I try to reconnect the ground cable and touch the pos. cable. The battery is under the truck in a drop down case, I may have to move it under the hood.
Too much serge from the alt.?