Hey guys,
I'm just looking for ways to take advantage of SCCA's update/backdate rules for xSP. I'm specifically looking for ways to change things that don't have a specific allowance by using the update/backdate rules.

Although I don't think I'll necessarily create a Nationals level car, I'd like to prepare it as well as I can reasonably do.

It might be helpful if I could get some specific changes between years and model lines that would allow changes not otherwise allowed.

Because I have an 07 Auto, I'm going to swap the rear ratio from the auto's 3.3 to the manual's 3.5.

Additionally:
Nismo aero package - questionable effectiveness at AutoX speeds?
Rearview mirrors - can remove '11 rules
Brembo swap - can use alternate brakes anyway
03 chassis w/ HR swap - way too expensive to consider for a while.
wheels - can use alternate wheels anyway
Nismo springs/shocks - can use alternate springs/shocks

Can anyone think of additional update/backdate allowances that might be helpful?

Did the Nismo have pillow ball suspension mounts? different geometry?