An auction at Bring a Trailer with a car fitting the same description (which could be the same one you are talking about) just ended at $105K for a very nice one - did not meet reserve.
So - at least $105k + the auction commission if the condition matches.
A GT5 did not well there for $141,500 recently.
So I would say somewhere between those two numbers.
You can see their auction results history here:
https://bringatrailer.com/detomaso/pantera/
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