Jig Borer retrofit

I have been given an old jig borer that I want to retrofit Linuxcnc to it. I plan on using AC servo motors on all three axis's and would like to use glass scales as the position sensors. What kind of setup would be suggested?

Not much to suggest since the chip shortage, but Mesa 7i96S and Mesa 7i77 can still be found.
If you can stretch for that, it is the most versatile combo for now, with plenty of IO, 5 step/dir and 6 full +-10V, another spindle, 7 encoders, etc etc.
As for drives, i have no clue, sorry.

Thank you for your reply. Where can I find information on configuring the ethernet based Mesa Cards? Peter Wallace suggested this forum.

forum.linuxcnc.org/27-driver-boards/3559...ethernet-mesa-boards
-
Peter Wallace is a great man.

Or consider ethercat servos with dual closed loop in the servo driver.

E.g. Delta A3 series.
The linear scale attaches to the servo drive.