Mazak QT20 MPG encoder

I am busy retrofitting a Mazak QT20 Lathe .Currently trying to get the MPG encoder to work .
It has 5 connections to it and is powered by +-12 Volt.
*+12 Volt
*-12 Volt
*Gnd
*A
*B

How do I get this to work with with the Mesa 7i77 ?

Voltage dividers on encoder outputs.
Using 2 resistors for each output works fine, but it would be safer to also add a 4.7V zener diode to each divider output.
That is if using a high speed encoder input on the Mesa.
If using MPG inputs, probably can skip zeners.
Edit,
You should firt power the encoder and measure output voltage to be sure it does not output negative values.
Mine does not.

I finally got a chance to work on the machine again ,been offline for so long ..

So I need to divide the voltage so that I get 5v on the outputs ?

Do I connect these outputs to inputs 16 and 17 on software mode 3 ?

How do I configure all of the mpg stuff into linuxcnc ?