[Jeff Lee]

I actually did a lot of research looking for an untried combo. Back then you had to give NHRA $400 for the complete class guide and engine blueprint specifications. The '70 AMX, while I was always interested in, looked appealing after looking at it in the guides. And I looked at a lot of others too.
Some cars are picked for no other reason than it was laying aroound or the racer always wanted that type of car.
If you really know your stuff, you can look through the guides (now available free on-line) and find errors that will be to your advantage. There are numerous examples which I won't point out. Other ideas are superseded parts being allowed which offer much more to the racer.
If you don't want a belly-button race car there are plenty to choose from. Even if you want a belly button race car you will have fun and should be competitive. Just be aware some classes and some combo's require infinite knowledge and / or $$ infused into the car to be competitive.