Has anyone ever tried installing a bearing in the bottom of a Tbird distributor? They look like they were almost made for a 1" bearing.

While a bearing sounds like a good idea, the distributor shaft is end supported within the block.  The lower bushing in the distributor is expected to be a minor player in keeping the shaft ‘true’ in its body as long as the top bushing or support is in good condition.  I’d think a bearing at the top of the distributor would be of more benefit than one at the bottom of the distributor housing but that’s only a guess on my end.  If you go forward with this, let us know how it turns out.

Lorena, Texas (South of Waco)

Thanks for the input Ted, I see what you mean with the bottom of the shaft in the block. I took mine out because I was getting too much centrifugal advance and I wanted to inspect to make sure all was OK. I pulled the breaker plate and weights out and regreased everything but I have not pulled the shaft out. The top bushing is nice and tight. The bottom bushing has some movement. I'm not pulling the shaft out for now with the extra complexity of the tach drive and seal that I don't have on hand. I was given a std distributor to use temporarily but it is too far gone to resurrect.
Which direction is the gear pushed when the engine is running? I'm guessing towards the oil pump so that it runs on the machined face of the block.
I do want to strip it down completely in the future, just not now.
If I do decide to be the pioneer with bearing modification I'll keep you posted. Though caution would be the order of the day as it is mostly made of unobtainium.