B-Truck transmission for shorter gear ratios?
 

I have to ditch my N/A trans with Miata gears and 4.30 rear for an R-Box and 4.1 rear from a TII due to a planned significant power increase. I feel like I might want shorter gears later on.

I want to know if any of you guys have experience using the gears from an '89-'93 B2600 transmission and if so, what is involved with swapping.
Is the input shaft the same length, and does it have the same tooth count? Does a 2WD R-box work with only changing the bellhousing?

The gear rations are shorter from the truck at:
3.730:1 / 2.158:1 / 1.396:1 / 1:1 / .816:1

S4 TII is:
3.483:1 / 2.015:1 / 1.391:1 / 1:1 /.762:1

I know my solution might be finding the info for myself, but one of you might know!

Thanks!

my friend did a rotary B2600, and the trans is really close to the T2, the biggest difference is that the piston bellhousing puts the case on a 15 degree tilt, but you'd need to change that anyways to put it in the FC.

i think you'd be better off by putting the truck 5th in the turbo box, that gives you the closest ratios. the 3.7 1st of the truck is like a granny gear