ITR LSD into B16 Y21 transmission, speedo gear rubs on case
 

I can't tell, based on the part ordering schematics, what shims are supposed to be installed and where to put this LSD into my trans. I was told that the B16 differential bearings would work, but when I install the LSD into the clutch housing, the speedo gear is rubbing on the case. I read somewhere that ITR ball bearings are 19.5mm thick while B16 are 18mm thick. Is this true? If so, what shim(s) are necessary to install this differential? It appears that 2 ITR bearings and a shim would cover it, but only if those ITR bearings are truly 1.5mm thicker.

Re: ITR LSD into B16 Y21 transmission, speedo gear rubs on case
 

Isn't there a way to mod the case for it to work.
I remember seeing it somewhere, where you grind down one part.
Anyone remember?