1967 Dart GTS Whats it worth

The engine and trans were not vin stamped in 67. So you can not have numbers matching, you can only have casting dates that would be inline with the build date.

Ask the seller to show you what numbers match what.

Other than that without pics (both cars) and some documentation that the 67 is a 383 GTS, how do you expect us to answer?

Or look at it this way..... I have a gold watch with a brown band, would it be a fair trade for my friends gold watch with a black band?