I was just told there is a difference in wheel opening molding on a cutlass supreme and a 442, is this true?

 

Considering that a 67 442 is a Cutlass Supreme, the answer to that is no.

There are other grades of Cutlass that year that are different, as well as an F-85, but Cutlass Supreme wheel well moldings work for 442 in 67 as they are the same part.