Screws are 5/8" x 10 tpi not metric,
Unfortunately 5/8" usually comes in 8 tpi.

Is it definitely an Acme screw or square thread, acme has tapered sides at 29 degrees ?

Then are they both RH, LH or one of each.
Bugger.. I thouht Acme was square, and trapazoidal had the taper?

Anyway they are square and both RH, y axis moves correct but the x is opposite to the lathe (clockwise rotation moves it towards you)