Servo Driven tool changer - How to set up

I need a little guide on how to set up a tool changer. This is a new to me Okuma MC30-VA. I already have two machines running linuxcnc but both of them don't have tool changers. I'm aware of the carousel component but the way this is setup is kind of baffling.

 


1st issue is that the tool magazine doesn't have any sort of position sensors. No proximity switches. It's driven by an absolute servo and I think the tool pot position is stored as a rotary axis. so I need to put an absolute servo for that.

2nd one is the tool changer arm has an induction motor with a built in brake. it's kind of sticky and I think the brake is on it's way out. so I would like to put a servo for that too. Tool changer arm has 4 proximity switches (probably gray code)

I'm planning to use ethercat for this one and I think we can use 3 axis + 2 tool changer axis for this.
So how do I command these extra 2 axis with the ethercat. My initial thought is using them as two rotary axis with absolute encoders. But don't need them to be in the GUI. Can anyone offer some help?  

 

I'm working on a gantry style one currently....though might build a carousel so it's quicker/doesn't eat space.

Rough process is you remap the m6 code, example here github.com/LinuxCNC/linuxcnc/tree/master...emap/rack-toolchange

my idea is to run two extra joints for this. but don't really know where to start.