I use an open ended Torrington bearing in the housing, after using a chucking reamer to open up the top of the housing for a slight press fit. Then I press a sleeve onto the distributor shaft to bring its OD up to 5/8" to match the bearing ID. A little green LocTite 638 "bushing retaining compound" keeps both pieces firmly locked into place. Here's a link to the parts I use, plus a bronze thrust washer between the centrifugal advance unit and the distributor housing. Remove the grease cup and replace it with a 1/8" NPT zerk fitting.

Here's some Ebay links:

www.ebay.com/itm/266001913104?

www.ebay.com/itm/294530267665

www.ebay.com/itm/271315191874

www.ebay.com/itm/203911361123

If you don't have a lathe handy, most of the reaming and fitting can be done in a drill press. Use Kasenit to harden the sleeve before installing it on the distributor shaft if you choose to do so.
Jerry

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