I think you're going to have to compare the new hood and fenders to the original parts to determine which, if any, is made incorrectly.

If there isn't a problem with the parts, then the issue is with the frame/crossmember/ etc.

What company did the hood and fenders come from?

1950 Chevrolet 3100 (Ol' Roy)

1939 Packard Standard Eight Coupe (The Phantom) | 1956 Cadillac Coupe de Ville (The Bismarck) | 1964 Ford Galaxie 500 coupe |1966 Ford Mustang (Little Red) | 1969 Pontiac GTO (The Dishpit) I 1979 Ford F-100 | 1976 Ford F-150 (Big Red) | 1995 Ford F-150 (Newt)