XB4 2wd

[silverfox]

Just finished building my XB4 2wd and was wondering if anyone could give me a bit of set up advice?
Using an Orion s/c and a T&F 7.5T motor, what sort of pinion size would suit Goshen?
Also wondering about tyres-thinking Schu mini spike yellow at back and cutting down the front wheels and using the yellow cut stagger low profiles. Med inserts at the back and none on the front?
Any other set up advice really welcome, I've not raced 2wd for 18mths