Way out of my depth

[JAZZCNC]

Can't help if your not going to provide what's being asked. We are not mind readers and if you don't show us or tell us exactly what you have done we cannot help you.

It's not simply case of plug in BOB and away you go. If this is dedicated motion controller then just plugging in parallel port cable and using mach3 isn't going to work because it's designed to use it's own bespoke software that will have special drivers etc.
Mach3 requires exact settings so it knows where to send signals or recieve signals from. So you'll need pin layouts etc of the boards your connecting upto to stand any chance of working.

My advise for simplicty is to map out where all the wires go and bypass all the existing boards. Looking at whats connected then it's very basic system in terms of wiring so will be an easy job to connect to another BOB. However like I mentioned because using servos the PP won't provide high enough pulse rate so you'll most likely need motion control card which gives more pulses.
But just to get motion it's simple job to connect to BOB and PP. But first you'll need to know which wire goes where so get tracing wires.