OK, I ordered the HB diff and it came in today. It is not the same as the sportwerks/muggy diff. The diff case is almost 1/4" longer than mine, and will not fit my setup at all.
Well, actually, I ordered everything I needed to build the diff, plus the Kyosho spurs. it came out cheaper than getting the whole diff. Now, I don't need any of this stuff. Any takers, I'll make you a deal.
I didn't get the hardened diff from Mike. I ordered the parts for the diff. The most expensive part of the diff is the hardened spur, which I didn't need, so I got the cups, the hardened output shafts, the hardened gears and pins, etc. I got everything except the bearings, because those are standard and I had those already. I'll pm you.