Mesa card setup for 3axis fanuc retrofit?

Hi, first of all i am pretty new for all kinds of cnc stuff, and not long time ago i bought my first cnc machine. So I have a Takisawa MAC V2E 3 axis mill that currently has fanuc 10M controller that does not work, and I have been planning a retrofit since i bought the machine. The more I dig in to the different setups and mesa cards, the more different ways seems to be possible doing the things I want, but not sure what would be the best and most efficient way for doing stuff. So, here is specs and what i have little bit planned so far:

For the spindle drive I am using the fanuc drive. I have already found that it uses 0-10v for speed, and forward/reverse direction control inputs, and got it working with them. I have currently ditched the ATC, but maybe planning to use it in the future, when i get everything else working right.

Servos are for X and Y fanuc 5s, not sure about the exact model yet, but smaller than the Z servo that is 10S. I have attached pictures about the Z servo and its pulse coder, have i understood right that I cant directly use this pulse coder for position feedback with mesa? I need to replace it or use converter? Changing it to some other encoder is not mechanically a problem for me, atleast the pico converters would became pretty expensive shipped to finland.  

Have i understood right that the MESA 8i20 servo drive will be enough for these servos? Is it controlled directly from the ethernet or from the I/O daughtercard pins where the position feedback goes? (like 7i77 or 7i95)

I haven't got any computer yet for the linuxcnc, so should I use 5i25 or 7i92 or some other? Or should i use some kind of ethernet breakout board and all ethernet?

For the encoder input and all other I/O, what board would be the best? Right now i am planning to run just the 3axis+spindle and all the relays and inputs for tool change/coolant pump, door switch, axis swithes? etc, but for future i have thinked about some stepper motor driven 4th&5th axis, and the ATC. 
   

Thanks for your reply Andy,

The axis servo drive is a A06B-6058-H322, that is listed as a digital drive. Only the X and Z axis are moving right now when using JOG or rapid or handwheel, Y axis were working earlier but suddenly stopped, which could be a parameter issue because i was messing with them but did not have probably the machine specific documentation and parameters so its no good... I tried to scope the Z axis pins that are coming from the NC, if i remember correct, there were about 6 or nine PWM signals (all 0.5ms apart if i remember correct), and 2 waves +- (they moved somehow apart from each other, if i remember correct it was from high point to high point 2mm travel of axis. I could scope the signals again with 6channel scope if this sounds somehow usable with linux cnc.

 Yes, spindle servo drive is 0-10v and direction. Its pinout seems to be much same as in the "Centroid CNC
Centroid Fanuc CNC Retrofit Installation Manual CNC Retrofits" (picture)

 For now Im not sure how many smart serial i would need. I know that I would need to atleast have: 
-3axis limit switch?
-E-stop
-door switch
-xyz encoders-signals and controls for/from spindle drive unit?
-coolant pump relay-tool changer pneumatic (2 relays)
-and for future, if i use the original ATC, it has 6 hall position sensors, servo or stepper motor (not sure which one, i have its original control but no documentation found anywhere in the internet, and it had a fault too), 2 pneumatic cylinders (so four relays)
-4th/5th axis stuff. But probably these (and the ATC) needs more boards for all I/O, so i won't be needing them anytime soon.
-and all the necessary buttons for user panel.. don’t know yet either how many would I actually need.. 

I’ll have to take a deeper look in to that encoder thing. I found probably the same discussion about these encoders, but it looked to me that it was a no go. I already ordered one Omron PNP 2000p encoder, for testing if I can’t for some reason get the fanuc ones to work. My goal is (like it seems to for many others too) to get one axis drive to work first, and then do the rest if the first one seems to work properly.

 

Oh, well there is run forward and run rewerse pins that goes to common when actiwated, and the spindle speed sure is 0-10v, I have played with these with jumper wires and is confirmed.

I have done lots of thinking and research, now I think that i would first go with the 7i97 because it has pretty much everything (and the 7i77 is not in stock anyway, and it works (if i had understand right) with the spindle drive communication, and i can wire my encoders staight to that, and also i can hack up some cat5 cables and connect them to that too for the 8i20 servo drives too?..

I was also looking for granite devices argon drives too (again), but i would still need a bunch of mesa stuff to get it all work, so the price would be a bit too high maybe for my budget.

I think that I will order one of each 7i97, and 8i20 for starters, and try to get one servo working first, and look if i can get the original fanuc encoder to work, or will i need to change that to NPN type encoder and order more of those. The 7i97 could also be enough for the basic input switches/buttons, and controls the coolant/toolchanger relay solenoids. If i can get most of that work, then i could expand that for the stock keyboard/else i think