I am restoring a '66 Mustang convertible with a 200 CID with automatic transmission and power steering. I have had difficulty keeping the battery charged. With assistance from a retired Ford mechanic (he worked on the '66 Mustangs when they were delivered to the dealer in '66) and friends, we have changed the coil, the battery, installed new belts, wiring harness for the alternator, rebuilt the wiring harness under the dash and changed the alternator. In fact, just last night I replaced the alternator for the 4th time. The rebuilt one was checked by O'Reilly's and it checked out ok. But, when I installed it and returned to O'Reilly's it showed less than 12 volts. This is the same result I have had with the other alternators. We have also installed a Pertronix ignition system and an electronic choke. The car runs ok until the battery discharges. The lights are dim when driven at night. Remember I'm not a mechanic so if you have any ideas as to a solution, please try to keep the explanation simple. Any help or suggestions will be appreciated. The other local Mustang club members have run out of ideas. Thanks, in advance. Also, when the radio is used, after a few minutes, it blows the fuse.