P1 racing buddy club wheels are not that light, if you really want to go with the lightest wheel ...
go for the ssr spec c wheels, in 15"
If where you I will do this:
SSR spec c wheels in 15"
Light weight exhaust system (mugen, 65 pounds)
I'll buy some light weight seats, (recaro, spoon, bride) (oem recaros are like 40 - 45 pounds each)
After market exhaust manifold. 15 pounds, OEM manifold 28 pounds
SSR spec C Wheels, 8.5 pounds - OEM 15 pounds (and the most important this is unsprung weight)
Bride carbon kevlar seats, 9 pounds - OEM recaro 40 each
You can start with this, if your car is not a daily drive, remove the radio + speakers and air conditioner, with these you will loose like 50 - 60 pounds
Do the math