I am thinking they are the same car in the 2 movies, there are too many similarities. However, now I'm thinking the GTX was actually a clone made from a Belvedere or Satellite. I say this because it is missing a few options you would expect to see standard on a GTX (Mopar experts, please advise):
1) 120mph speedometer gauge - see pic (GTX had a standard 150mph speedometer gauge)
2) Column shift (console shift standard on GTX?)
3) Missing chrome brake light bezel (standard on GTX), however these could have been removed.
4) Missing chrome wheel-well trim (pretty sure standard on GTX), however these could have been removed.
5) Bench seat up front (not sure if GTX had standard buckets or not)
6) No competition gas cap and bezel (standard on GTX)
Anyone spot anything else?
The links to the videos are here:
Tommy Boy:
https://www.youtube.com/watch?v=U05y06ikKbIJoe Dirt:
https://www.youtube.com/watch?v=_Kvq0XEB3DI