Ball Screw mounting block

I am gettig ready to install ballscrews on a
small (and old) verticle knee mill. I am
new to this and trying to figure out the details.
I have attempted an ascii drawing below.

Basically I will bore holes on each side
into which angular contact bearings will
fit. The screw goes through the bearings
and the block and then a retaining nut is
tightened on. Is this basically the way to
do it?

Also, is there any advantage to having this
type of setup on each end of the X-Axis screw
with a little tension applied to the screw, or just
support the other end with a simple radial bearing.

Any thoughts appreciated.

Mike Gann

Bearing Support Block
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