Sounds like what I went through a few months back and it turned out to be the fuel pump. If it's the original pump and the car has been sitting for long periods of time (what Pantera hasn't), the diaphragm within is probably bad by now. Just because it won't PUMP fuel, doesn't mean it will leak fuel through (not much anyway — mine didn't).
For about $35 bucks you can get a new fuel pump and see for sure. The only down-side it it is not the easiest part to access. On the up-side, you'll have a new fuel pump and one less failure-in-waiting for the future.
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