[ozo]

If your ball bearing is in properly [for detent]
then, with the set screw out [the allen screw
with the brass end that screws in the ram]
hold the shell plate in place, screw in the
retaining bolt until firm. While turning the shell plate
tighten or loosen[center bolt] it until you have it
just free from binding the shell plate from turning.
You want it as tight as possible WITHOUT any
binding. It is just something you have to 'feel' for.
I think the instructions say snug it, then back it out
1/4 turn......mine seems a tad too loose that way.
Keep feeling it....and you will get it.
It is a bit funky, cause when you check it by turning
the shell plate, the bolt will turn with it. I do mine by hand
using only my fingers[center bolt] and don't use the allen wrench.
When I first set the shell plate down on the ball bearing,
I hold it down with two fingers, one on each side of the
bolt hole, then screw the bolt in until snug, keeping the plate
pressed down at the same time. That is usually too tight, so I
back it out a little...etc...til it feels right. You have to put the set
screw in the ram before you go turning the shell plate very much,
as you setting will change. PITA sometimes having to do that a
couple of times to get it right. And DO NOT over-tighten the
set screw, you will mash the brass end.