Use it for parts or resale??

Ok guys I figured I would get your input on a car I'm looking at buying. It's a 74 Dart custom 4 door with 318, auto trans, air conditioning, front disk brakes and vinyl top; 93k miles.

Car is completely rust free, factory paint, factory top, all numbers matching. 1 owner car with original owners manual and build sheet. The only bad on the car is a small transmission leak and the front seat is cracked on the driver's side. The paint is good and so is the top.

Question is, do I kill it for the drive train, brakes, rear end etc to build on a duster or try to resale. If I resale what would you approximate the value at, I know this is hard without pictures but I will add some on here when I pick the car up tomorrow.