For those that have installed a 200r4...

as long as you match the output angle of the shaft to the differential yoke, youll be OK (minus about 3 degrees) ie. the trans is pointing down 4 degrees, you position your diff pinion to be up 4 degrees. This is a simplified example but in the real world, you want your pinion down a few degrees to compensate for spring wrap under acceleration. Does the 200R4 have a thicker cross sectional area in the tunnel? Im sure it does as the 904 is pretty skinny back there.