1969 Quarters on 1967-8 Body Shell?

[Mean 69]

This may have been covered before, but how difficult is it to graft a 1969 rear body onto an earlier donor body tub? I am in the begining stages of building a new car, primarily for road racing (as in dedicated, non-street car) but am finding it difficult to find a decent donor 1969 for the project, there seem to be more of the earlier cars available, including Firebirds. I don't really like the idea of molesting a car, but I am set on the 1969 lines, and it is going to be a race car anyway.

Anyone done this? It would seem that the major pickup points would be the same, but I don't know if the roof changed, making it less feasible to consider. Any input welcome (or, if you have a decent body shell sans fenders, doors, etc, I'm interested, please PM me).

Thanks,
Mark