bearing with pressure screws? You mean bearings or joint bearings. .
What type of bearing are you using?
how and where is it mounted?
other question... Have you read anything on the skf site on the mounts?
I'll take you back the first line:
"heads y do not allow axial shifts"
The rest you find
quiDeduce it's a y-like from the first post you did.
so in the bearings the bearing is already stuck axially, as you should also see from the section. the shoulder can serve for a match of positioning of the tree.
the elastic ring I would say that it does not serve anything except to weaken the tree; if the axial shift is enough to disconnect from the bear the ring if you eat it at breakfast. . .
in case axial efforts are impegantive perhaps you should think of adopting another type of stand. maybe with traction compass
of course from a sentence and a half to understand what is needed is difficult
put a sketch of your solution