There were about a dozen of these things built in the '80s by Mike Cook in Norco CA. Most have been re-converted back to 351Cs, once the owners found that they weren't any faster and were quite a bit heavier than a 'std' Pantera. Drag racing a Pantera is not very successful as with any independent rear suspension car. As far as I remember, the gearboxes were left stock and worked just fine that way. No particular advantage or disadvantage socially- Kerry Shaw regularly runs his at Willow Springs race track with the TPOC crew.
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