Hello mpryne:
I have no experience with the Bandit control. It is a really old control. If it had DC servo's, with a +/- 10v signal output to the amplifiers, you could use the servo's and motors, and retrofit a new controller such as the Vital Sysems dspmc.
If it is stepping motors, I would suggest a total retrofit.
The Vital Systems controller is an excellent unit, and very capable, plus it has been engineered to work with Mach3.
That's all I can suggest at this time.
Regards,
John