I'll get them apart and see what is what. I've had people tell me that number crosses to anything from 1 1/4" to 1 1/2" so I guess I will see when I get it apart. It's soaking in PB Blaster at the moment.

1954 Chevy custom 261CID, T-5 5 Speed.
1952 Chevy 6400 2 ton hydraulic flat bed.