I have a buggy with an 87 mustang motor in it i recently switched out the battery, it ran and started fine, so i unhokked it let it sit came out a week later installed a tach went to start it hooked my battery back up, the second i got the cables on, a wire that runs from the alternator to the pos. side of the soleinoid melted. :mad3: And now nothing works? Any ideas would help imensley!! Thanks

One thing that I can think of that would melt the Battery cable is a direct short in the starter. Everything else is fused and would blow a fuse before doing that much damage. Or possibly a damaged alternator that grounded out.
Anything electrical in the engine/chassis should be fused and not draw enough amps to melt a large cable.

The drawback to such a meltdown, is that you could have cooked many other items. If you computer was pluged in at that time, it may have damaged it or some of the sensors.
Try disconnecting the starter and the alternator, and plugging in the battery. See if anything turns on, besides starting the engine. Does your radio work? or other items? If they do, reconnect the alternator main charge wire and check again. If that works reconnect the starter and see what happens.

Good luck... .and let us what you find.

Brian