I'd convert it to CNC (I'm actually keeping a lookout on ebay in the hope I can pick one up cheap), as I think they're an ideal size. Not too big that a conversion is going to cost a fortune with big steppers/servos, yet large enough to handle dealing with big lumps of steel.

The main leadscrew should be poorly fitted at the belt end, as it should be free floating in the coupler. End float is controlled by the cheap and cheerful bush type set-up at the handle end, which as standard is useless. However, the collar on the leadscrew at the handle end, is the perfect size for mounting two angular contact bearing back to back in a new housing, which makes a huge difference to backlash.
And the main nut is a split nut, with a bolt to adjust out play, however you've got to maintain a couple of thou play in it, otherwise it just wears quicker and/or binds.