Charlie is right- 'GTS' is simply a model of Pantera in Europe, and since Ford abandoned the Pantera project in mid-74, DeTomaso basically built cars to order. So that thing could be a street version of a Gr-3 club racer, or it could be a totally stock plain-vanilla Pantera of that year, or literally anything in between. Only an inspection by someone who knows what they're looking for will be able to tell.
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