Control system for Harrison M250 CNC

[Chaz]

I've just bought a Harrison M250 that has factory-fitted CNC system, but the control system didn't come with it. As a result I essentially have a lathe fitted with stepper motors, adjustable stop switches and an encoder on the spindle. I know enough about electronics to sort out drivers for the motors etc. but being new to CNC I really don't know where to start with the control system - I gather that Mach3 is a good option for the SW but ideally I want a controller that will use the features of stop switches and the spindle encoder - it would be easy to use just the two motors but it wouldn't be long before I wanted to do something like thread cutting, and as the lathe doesn't have a full set of change wheels I might as well put the money into improving the CNC features.
So, the question is whether anyone can recommend a control system that would work with Mach3 and interface to the stop switches and spindle encoder.
BTW FP on MYCNC, so Hi to all!

Ive just installed Centroid Acorn on a Harrison M300. I'd never look at Mach 3 again, not the same league.