Since you don't have a car to build right now, let me say just a couple of things in defense of the generation ! cars. Those '60-62 Valiants are lighter than our car and will be faster with any given drive train. They have full rear wheel openings, so you don't have to worry about the slicks rubbing the inside of the fender panel.
We built a 4-door because we decided to build a car on Sunday and Freddie's wife found a '64 Valiant in the paper the next day... and he didn't want to spend a lot of time shopping for a 2-door (which are 25 pounds lighter) and got it in fairly good cosmetic condition for $700.00.
We can't get a lot of tire under the back of it (9"-wide, 26"-tall 15-inch slicks are the limit without moving the springs and/or tubbing it) but otherwise it's been an ok car to build.
But an earlier ('60-'62 car) would have been better. We spent a lot of time and effort getting a reasonably-wide tire under this thing; hopefully, we're gonna need it!!!! :prayer:
Good luck!!!