Hmmm, looks like at least one of my cars may fall in between the rules. My '64 Galaxie has small tires and a stock leaf spring style rear suspension. It also has a weld-in Art Morrison front clip based on the Mustang II design, to make more room for the engine. It looks like it would fit in Modified if I got approval for the welded in front clip, but then the rear suspension being stock in origin won't work. In Super Street the rear suspension would be legal, but there appears to be no welded-in front suspension components allowed. I guess it would fit in Unlimited
My 69 Shelby Mustang clone has small tires, but is back halved with a four link. It retains the stock front frame rails, but has a bolt in strut conversion kit from Fatman. To make room for the SOHC the shock towers are cut out of the car, and the top strut mounts are welded on to the forward roll cage extensions. It looks like it might fit in Modified, because it does use the stock front frame rails, but I think I'd better check with Hot Rod to be sure since the factory shock towers are gone; if they consider them part of the frame rails, Modified is a no-go. It also might fit in Pro-Street with a special approval for the front suspension, if I decided to put big tires on it. But I hate to do that, because the wheelwells are radiused for a 29.5" diameter tire. I'd rather not re-do that bodywork.
Looks like I might be a special case again this year<sigh>. After last year's one day and out performance, I was thinking about coming back this year with three cars: My Galaxie with the 520" SOHC, my Shelby clone with the 585" SOHC, and my 69 Mach 1 with a new 530" High Riser engine. Figuring at least one of them would finish

The Mach 1 fits into BB/NA street race with no trouble, at least. Hope I can get the other cars into competitive classes; we will see what Hot Rod says...