A quick look shows stuff you need to have for IT; headlights and wiring, wipers- motor and wiring, stock bumpers, i ampretty sure that you need most of the stock wiring harness. Along with stock brakes, trans- flywheel etc. Stock glass.

Stuff you cant have; Holes in the hood, non stock intake- carbs etc.,

I dont know where you are in the SCCA country. Maybe check the vintage group and see how much of this can run, maybe check the ITEZ rules ,if you have them in your area.
Call your local race director/chair, and or tech guy and explain your situation to him. He should do his best to help you find a class for your car. Maybe ITE, SPU or some catchall class will get you started.
Last look at NASA rules , WRL rules are very open but have very few races.