Odds are that the problem stems from SOMETHING you did. I'd first look at the door grommets where the power wire comes through the door and jamb. What concerns me is, no fuse apparently blew, and that power wire is fused! As you probably know, the Pantera is THE most messed-with sports car on the planet, and some former owner or bootleg-mechanic could have jury-rigged anything up to a nuclear generator in there over the last 32 years. I suggest getting out your VOM (volt-ohmmeter) and starting from the window motor power wire, trace out the line back through the switches to the fuses. As stock, it should only be a few feet of wire, but as I said, by now anything's possible.
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