All the above are worth checking, but a huge proportion of brake-pull in a Pantera comes from one piston in one front caliper sticking from varnish build-up. Pull a front wheel and have someone step on the front brakes while you watch closely for ALL pistons on one side to move at once. Then check the other side. There are 8 pistons and only ONE slightly stuck will cause a pull. Its caused by a car sitting dormant for long periods of time combined with the brake fluid NOT being changed at least yearly to eliminate moisture build-up. Fluid leaks will also do this but its far less common than plain ol' varnish.
The only possible fix is simple and cheap but is also one of the sloppiest, most miserable ways I can think of to spend a weekend: R & R each caliper, pump out all 4 pistons, scotch-brite the chrome plated piston surfaces & inside the bores, and reassemble, then bleed with fresh fluid. Do NOT separate the caliper halves and do one side at a time so you always have an assembled model. Costs nothing but labor (and several showers) but there will be quite a bit of effort! Some vendors will do a core- exchange on your stuck calipers; call around.