New to the MR-4BX

[Bike Racer]

Hey guys, I just picked up a used BX, and I'm just getting started working on the setup. I have the original version, not the Factory. I have several questions.

What is the stock anti-squat setting with the little aluminum spacer? How much do the other spacers add, there are 2 sizes. It would seem that flipping the rear toe mount (pivot) would affect anti-squat too, but how much??

I've read some about the longer rear shock shafts, and taller rear tower?? Anyone have part numbers?

I've seen the B4 CVD mod, is everyone running that mod, or are some doing OK without?

How about gearing with the stock 84T spur? I'm running anywhere from a 9x1, 10x2, 11x2.

I'm from the USA, and mainly race indoors on mid to high bite clay tracks with pretty big jumps.

Thanks for any help!
Jeff C.