I'm 6'2", maybe 6'3" and have a 32" inseam. Right now my head has about half an inch clearance from the roof. I want to track my car, and will almost certainly need a helmet, which probably will not work unless I slouch, which is probably going to be an issue. I'm praying that I could get at least an inch or two, but it already feels really low in the OEM seats.

That depends entirely on the seat and bracket tbh. Have you done the seat mod to lower it 1 inch?

I have not, I didn't know that was a thing

I don't know if the instructions are 100% the same for the V35 seats but the theory is the same, loosen the nylock nut, remove washers/shims, reinstall the nylock with less thread reveal so the worm drive gear has more range.

This thread will give you an idea how to do it, I've never done the mod because I'm 5'10" so there's no clearance issue, instructions might be exactly the same.

https://g35driver.com/forums/v36-diy...at-height.html

I think that's for the sedans cause my seat doesn't come apart like that and from trying to follow it just doesn't look the same

It's still a worm drive gear, I just linked that thread to explain what will need to be done.