For the two door near you, how heavy is the "heavy bodywork"? Is it frame/unibody bent due to rust or accident, or is it just rust repair for appearance only? The picture you posted doesn't look too bad, but I bet there is a lot more damage to be seen up close. As well, is all the exterior trim there, and what does the interior look like?
I would just point out to him that the collectibilty factor is close to zero, when the engine and transmission are not numbers matching, and that this isn't a Hemi 'Cuda convertible. The side pipes don't help collectibilbity in any way, either.