Sounds to me like you really want a 67 or 68 fastback but a 67/68 convertible would be ok. Right?
Here are my unsubstantiated comparison. Assuming equal condition at each point and similarly equipped.
$10,000 $5,000 Project
$15,000 $18,000 Resto cost
$20,000 $15,000 Driver quality value
People will say the numbers are meaningless, I agree. My point is an equivalent condition project vert will be less than fastback. The cost and effort to resto the vert will be higher than the fastback. The finished value of the fastback will be higher.
Lastly a vert is NOT a cheap/low maintenance date. Been a vert lover since a teen ager.
To me verts are like women. If you like em you can't live without em. If you don't like/love they can be a big PIA!
My '64 1/2 vert. Ordered May '64. D code 4 speed, handling package, caspian blue, accent group, Ford blue manual top.
'68 vert. driver. Owned since Apr '78. C code AT, AC, PS, P disc B, PT lime gold, standard black interior and top. NOS RF fender and left quarter.New top and folding glass.