Not unlike the appraisers on Antiques Roadshow, the value of a project rises with the number of genres and interests that the subject can cross. The name value is strong, MPC collectors, Drag Builders, nostalgia...

Never mind that the GTO and Mustang were unlikely Pro Stock cars - a Firebird would have been a much better candidate - there is a lot of interest in the distributor and mass market retail channels for those names, regardless of the box contents. And believe me, they don't give a fig for accuracy so they would do just fine.

What I will say: as a 12-year old builder gradually improving skills, those kits were a bullseye, at least for me. They looked a lot better than the effort invested when they were done, and they really have a nice 'pop' on the shelf.

But that's just me...