sounds like an alternator to me bro. those things are NOTORIOUS for going out in fords...
or... do you have a system in your car? funny as it may sound, haha... this happened to me:
the leads to my system from my battery were all fubared and stuff (on the 86) and one of the leads just happen to be lose which was draining mad power. well, took it to vatozone, they recharged the battery, etc etc.. didnt work, we replaced the battery, replaced the alternator.. nada. so, haha.. then i see this lead, and im like AWWWW WTF!!!! so i just plugged it back in, and VOILA! power!
but i bet its your alternator.