My '30 AA axle had roller thrust bearings and the kingpins had a BB and Ford script on them. I tried finding new sets, NLA. A local NAPA guy and their bearing distributor rep spent an hour and a half with me looking. After several soakings in kerosine and acetone the old bearings cleaned up and after oiling worked smoothly. I could use them if necessary. I did a lot of research and for those of you who think any bearing supplier can match you up a new bearing with your old Timken bearing number you are living in the past. Not so anymore. I did find a thrust bearing (ball) from Grainger that looks like it would work dimensionally, but pretty pricey. In the meantime I found a NORS AA kingpin set at swap meet with lots of "staining, i.e. surface rust". It has ball bearings. The A parts are a lot easier to find.