I have a question about a bearing and collar that I'm trying to put on a 149 S/N below 480xxx. The collar is P/N IH=60071 and yes I have been all over the FAQ and I guess it Charlie's FAQ on how to install.How does it lock when rotated? When I mate them together thy just spin and I don't see how they would tighten up or lock. Maybe this style doesn't lock. If that's the case, do I tighten the set screw to the shaft in the key groove? Kind of stumped on this. I searched the archives and didn't see anything that pertains to this. I would appreciate any help on this. Thanks.