Denford Milling Machine

Hi guys,
I'm new to this list and I've been browsing the archive.
I've been asked by my local school to see if something can be done to
upgrade a Denford CNC milling machine which they received as a
donation some time ago.
It has an early CNC controller by Northeast Electronics,
which has all the programming in PROM and communicates using a
rudimentary serial port.
I've looked at the circuit diagrams and the hardware and it
seems to have dedicated stepper drivers with step, direction and
boost inputs. There are also limit switches on all axes. The spindle
is a 1/2HP 3-phase motor driven by a variable frequency inverter.
I'm leaning towards Doug Yeagers CNC-Pro to drive the
existing hardware. Has anyone any experience of these machines? Any
advice will be gratefully received.

Philip Mac Cabe