At 6' 1" you won't have any problems that cannot be fairly easily solved. I'm the same height and 200 lbs and I fit a stock seated Pantera okay (as long as the pot holes aren't too big). Find one with dropped floor pans or plan on doing that as a mod and you can gain up to another 3 inches. Then you can even wear a helmet for track days
A lot will depend on the individual car; as you know Pantera's are as individual as the people that drive them and many have aftermarket seats of varying style and quality, but even then it's pretty easy to overcome or change them. I put Corvette seats in my '74 and to gain room simply threw away the sliders and bolted the driver seat to the floor. Heck the wife didn't want to drive the thing anyway
Good luck with your search and welcome to the PIBB.
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