There is, or used to be, an Accel distributor that was a better fit for the Pantera. Check: www.panteraplace.com The Accel distributor cost less than MSD version. I just went through this size problem this spring, low profile and small cap.
I bought a Ford 1976 distributor for a 460 CI. it drops in and has the magnetic reluctor so there is no point bounce or cam wear to have to deal with. Since there are no points the bearing doesn't work hard and sleeve bearings are fine. This is the fix that the guys used years ago when there weren't many after-market distributors. I paid about $55 from NAPA. Not all is lost ... You can sell the MSD on Ebay, they re-sell very well.
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