Hurco KMB-1 Retrofit options

Ok so I just got an early 80's KMB-1.  Looking at more cost effective option to retrofit a newer system.  Has anyone ran the centriod Acorn on this mill.  Researching to see if most of the electronics and power can be removed from the machine and install Acorn using stock servo motors.  And use a VFD for the 3phase spindle motor.  I have a cnc router with Mach 3 and not a big fan of it but would use in a pinch.    

Tommylight, I am just looking for options. I will check out the linuxcnc. What I am really wanting to do is strip as much of the original boards and wiring and go with something newer and just run spindle off of a VFD. Just was wondering which boards and systems will work with original servos.

I did an SM-1 (the knee mill cousin of the KMB-1) with a 5i25/7i77 combo and reused all servos and drives. I think the only electronics I added were the computer with 5i25/7i77 and a VFD for the spindle. I did away with the vari-speed mechanism in favor of VFD control.

I'm another with a KMB-I. Mine is 1981 B control, and is fully functional as is. Pretty much original. Parajust VFD, ServoMate ±12V signal Servo boards and has the same Electro-craft 90volt brushed motors with built in tachos and Litton 200 cpr quadrature encoders almost as described here. forum.linuxcnc.org/12-milling/39662-hurc...s-cnc-update?start=0  It has the Bristol Erickson quick change #30 spindle. Oh yes, I do also have Buddy Maughon's tape emulator. It had stood unused in a private workshop from 2001 to 2021. Had to replace a variety of electronic pieces in the control and parajust to get it to start and run, six month entertainment, prodding with a scope and voltmeter, but worth is as only run for 1938 hours, so straight and true. Oiler, spindle, brake safety pressure switch coolant systems, flood and mist etc all in good order.

My requirement is 'only' that I want to be able to send it some G-code so I can machine some weird 3D shapes.
So, I'd like to be able to swap to a Linuxcnc front end, but in a way I could perhaps swap back to the conversational system I have come to admire and like. I guess in one dream, maybe a Hurco conversational front end could be built for linuxcnc...
Yes, I know the obvious solution would be a B to BX controller upgrade. Would I think do all I need, but the current price is so much more than what I paid for the whole machine, I'm having a hard time justifying that kind of expenditure.

So, I've a running linuxcnc 2.9.2 app as well as mesact installed on a Raspberry PI-5 and a 7i95T ethernet on order from JT, too many axes I know, I am also aware the the three shaft encoders will need more pulses, and can handle that as have already fitted one USdigital item to deal with the Y encoder that had a chip out of the glass scale and several lines missing. The USD part needed a mounting base making, but otherwise worked straight out of the box. 
But then I kind of missed the point with all the daughter board options, and I would appreciate some clear sighted and informed opinions on which ones I really need to make this dream a possibility. 7i77 or 7i83 for instance might be ok for the servos, but then they've 10V versus 12V output that the ServoMate is expecting. Secondly I probably also need maybe a 7i73 to interface with any jog generator and buttons on the panel.

Apologies for writing so much, but I'm hoping that the detail will be helpful to someone some day.

Fingers crossed.