[double0010]

...be turned into a hardtop?
Hmm ok thanks. I guess my next question would be what if I can find a frame of a 67 hardtop, can everything from the sedan switch over?
minus the doors and door windows

 

[blanderswake]

Sedan and hardtop roofs aren't always the same shape. You might put some hardtop doors on and the windows won't fit the opening correctly. Don't worry, a '67 sedan is cool, too.

 

[Paul D]

The amount of work needed would be extensive. The reason is that the door pillars are in integral part of the body and frame, holding the roof up being only part of its function.
Given enough extra steel you could probably make the underlying frame strong enough, and you could rig up something for the roof but you would almost certainly look back and wonder "what was I thinking"!