Custom Chrome uses them on their transmissions as new.
I see them as a bit of a bandaid when used to stop the fourth gear/main seal leak, but don't have any issue with seeing 'em on a newly rebuilt trans.
That Canadian dude might be somewhat hard to find. I published his name here a while back and he asked it be taken down.
The spacing issue is a pain in the ass if you're attempting to use a mainshaft bearing support on a Shovel.
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