Sadly, niether Boca nor Avid has the size bearings I need.
I spoke with glassdoctor a little while ago and he wanted some pics, so here they are:
This image shows the insides of the various spurs. From top left: CRT.5, Kyosho, and Hyper 8. Right away you can see the CRT spur is shaped differently and has less depth.
This image shows the top view and you can see the bumped out part of the CRT diff that makes it so low profile.
This one shows the difference in collar size/depth.
This one shows one of the outdrives and how short it is. This is why it won't fit on the Kyosho spur. If I shave enough off the Kyosho collar for the outdrive end to reach the other side, there isn't enough room for the bearing. I can't use a regular 1/8th scale outdrive since those are made for much larger dogbones.
There is no O-ring in the diff, just this plasticy gasket. Maybe this is why there are reports of leaks? I replaced it with 2 of the Ofna paper gaskets.
This one shows that even when the collar of the Kyosho spur is shaved down, the other end of the outdrive is still too short. Any more shaving and the bearing on the collar won't fit.
This one just shows the stock bearing on the Kyosho. Doesn't fit well obviously. :)
Hope this helps you visualize what I was talking about glassdoctor...