Bronze distributor shaft gear wear
I don't think the replacements have to be sized, I've never sized one.
Some are made with an oversize internally for the jobber crowd. Just hammer them in and go, it saves time, but you have no control over the internal size. Chances are they will be made with a looser tolerance internally, to avoid any binding issues, once pressed into the bush bore.
I like the ones that require burnishing.
Always check the gear end of the roller cam. If the gear teeth cuts are not smooth, then you will need to get in there and clean them up/ polish them.
Check gear height of the intermediate shaft.
I don't use a collar on the bottom of the distributor shaft. I make up a long alloy sleeve that runs all the way up to the base of the distributor body and then mount a Torrington bearing between them.
Good lubrication in that area is a benefit as well.
