Buy the Gen 1. The later cars will never have the value of the 61 - 64s...and they just don't look "right".
(gen 2)
(gen1)
These are 40 year old cars. Your best bet is to buy a car that is in very good cosmetic shape (especially the glass, the base metal (forget the paint) and the chrome, especially the chrome) but barely runs.
Then jerk the original motor/trans (don't discard....just set it aside) and drop in a 1995 or newer Ford truck engine.... a 302 would be perfect. You'll have more performance and bulletproof reliability.
Use the original AC/heat controls but gut the rest of the system - and be prepared to have chronic window problems till you buck out for rebuilds or modern replacement mechanisms.
Door and trunk key and lock mechanisms are also made of unobtainium.... good to get a pretty intact body from say.... North Texas.... and go from there.
A great recent set of articles on the joy of a vintage driver is a series of 1956 or so Cadillac articles in last fall's road and track magazine.
Seriously, if you're looking for a bargain vintage driver.... get a boat.... super-clean late 70s TCs are still available around $3500... and they don't need virtually everything.... but get a good one.... 30 years is forever to a car.
Here's a picture of an example.... 1977 MB 450... 68,000 miles....
thousands of hours of searching.... I paid under $4000 for it.
This car, with proper storage, frequent low-mileage use and proper freshening, is as reliable as a new one. You can find Lincolns like this....if you're patient.
Make sure the car you buy has been driven regularly. Cars die with disuse.