I'll attach pics of the two common styles of follow rest...one bolts to the top of the saddle and straddles across it while the other bolts to the side of the saddle. Since they're mounted to the saddle they follow the cutter as it moves along the work to oppose cutting forces. A steady rest clamps to the ways and stays in one place so that you can work farther out from the chuck...think of it like a chuck extension so that the chuck is now farther away from the headstock.
Most of the Enco lathes seem to use the follow rest that bolts to the side of the saddle, like the white one below.
I went back and bought the other follow rests, but was honest with the seller and said they weren't for me so I didn't get quite as good a deal, but he was still very fair with me. I got some decent ballpark measurements but can get more accurate numbers in the next few days if someone is looking for one. I suspect these were for 12-13" lathes.
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