Factory frame from axle to axle
Steel roof and quarters
1/8 mile pro tree
There are only two axles and both are in the rear, lol I know what you are saying but you need to be VERY specific or you will be having this argument!! The first two rules leave A LOT open to interpretation. A factory roof and quarters with stock frame could be a 2100# Datsun 240z too!! IMO, weight, tire, Regal body, 109 block and first to finish line.

BTW there is no way in hell I would race this class!!
Factory Regal or TTA Body
( Factory firewall, 50% factory floor, 2 seats, all body panels present, working lights )
Factory frame from front hub to rear axle
Max 275 / 28.5 X 10 tire
109 block
1/8 mile - .400 pro tree
Stock suspension pick up points, or are you going to allow 4-link and/or ladder bar. It doesnt matter either way to me as I believe the rear stock suspension is as good as a ladder bar or a parallel 4-link on the 275 radial. On the front however you could put a strut as the factory front suspension is very limiting. I'll have to see how much trouble it is to put a 109 in mine in case they they wont let it in TSO, which it looks like they are not going to allow it.