Pablo works just up the hall from me over here in Cheater's sweat shop. So when I got an interoffice memo from him about doing-up an Igarashi "Hemi", I got busy. Oh and, it looked as though I *might* be able to actually install a 5mm bearing in the end bell, but I was worried about both clearance and even more about reaming-out the existing hole in the hard-but-brittle end bell's phenolic-like material...whatever it is. The build involved installing C can motor magnets (*strong and well-matched ones courtesy of Cheater), as well as bearings on both ends and a new H-Power can drive arm.
For the can shim, what's needed is a can that has the welds and cross pieces in the right place so it all doesn't fall apart after cutting-away the stuff you don't need/want. Here is one that works, there are others too, but many of the modern C cans have so little material they won't work at all. I do the thinning of the top, bottom and curved sides before cutting so the man-handling is less likely to ruin everything. The top and bottom flats are done on a small bench top belt/disc sander, the curved sides are done on the lathe. The sharp corners of the can-shim after thinning need to be radiused to fit the inside rounded corners of the larger D can. After I'm pretty sure by testing then fit that the can will slide into the larger D can, I cut away the extra material and de-bur everything because little bits around the edges can make the whole thing not work, and you don't want to find that out while trying to insert it...and only getting half-way in! (*I found that out the hard way ). When sure or pretty sure it will work, I epoxy the mags into the new can-shim, so that whole deal can later be installed in one shot.
For the end bell, my biggest concern was that the hard brittle material would crack...and there's not a heckuva lot of room to work in there. I used a tapered hand ream SLOWLY until I got fairly close and then finished it off with a 5mm chucking reamer. Also, as the end bell was...it had a recess for the old bushing that was too small for the 5mm bearing flange. I inserted a temporary 5mm oilite on the outside as a centering device and then used and end cutter on the inside to cut a new larger recess...again SLOWLY. After all that I epoxied-in the new bearing and the Hemi's end bell material should make for a good bond.
Now I can install the magnet/shim assembly so it's centered in the existing can holes so it all looks like it's supposed to be there, and proceed to press a stack and space it for the hemi's new strong magnets. BTW, these magnets you sent are nice and strong and really well-matched. This all should make for a very smooth and fast, as well as definitely unique Igarashi that looks fairly stock on the outside.