HELP. 5.0 won't hold a charge

did you fry some fuse links??

i did that once, fried a fuseable link, wire should be comming off the solenoid. wire should look fried. check it out

You may have melted a couple of wires together somewhere.

Reversing the jumper cables usually takes out the alternator. It destroys one or more of the diodes inside the alternator. To check this out, look for 12 volts at the black/white wires on the back of the alternator. If the 12 volts is present, the altenator is toast. If it isn't, you may have opened up the alternator fuse link that lives inside the wiring harness near the starter solenoid.

See http://www.autozone.com/servlet/UiB..._us/0900823d/80/19/59/5a/0900823d8019595a.jsp for wiring help.

A 3G upgrade would be a good thing to do at this time. Here's websites with pictures of the 3G (94 Mustang and later 130 amp alt) installation procedure...

See http://www.geocities.com/smithmonte/Auto/3G_130A_Alternator_Upgrade.htm - all the tech data you could ever want to know
OR
http://www.mustangcentral.net/tech/alternator.html - excellent pictures of installation

See these sites for the right way to do the wiring. Some people will tell you that you can skip the wiring upgrade, but it will catch up with you sooner or later. A fire in the wiring harness is ugly and expensive.

Under no circumstances connect the two 10 gauge black/white wires to the 3G alternator. If the fuse blows in the 4 gauge wire, the two 10 gauge wires may be overloaded to the point of catching fire and burning up the wiring harness.