What is your budget and willingness to accept mods etc.? I do believe the value of a GT5S is somewhat in it remaining mostly stock ( except where the engine is concerned). Things like original Campi wheels add a lot of value and are getting hard to obtain. Are you willing to consider something that requires work or looking to obtain a fully sorted example?
Be wary of conversions executed with Hall panels as they were reputed to not be exact left and right, but then many originals car aren't either.
I know of a 72 GT5S conversion that requires some work, can probably be had in the mid $40K region.
Julian
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