So if anyone is considering buying one of the many used renishaw probes on eBay - here's my conversion to work under PathPilot with TTS.
I started with a $69 Renishaw MP3 on a CAT50 holder here:
Attachment 345140
After taking the pieces apart I removed the Inductive module (unscrews w M4 screws) and cut the 2 wires (white(+) and red(-)):
Attachment 345124
Then I drilled out the hole to 0.6in and wired in a 3 pin din connector:
Attachment 345126
There are only 2 wires in the probe the white and red - these connect just like the tormach or wild horse probes although the White goes to the +5v, and the Red wire to the ground.
For the LEDs i drilled out the smaller holes below the DIN connector and glued in some white LEDs.
The circuit is simple, one led + 1K resistor connected across the red/white wires.
Attachment 345128
Then I make an adapter plate that screws into the previous inductive housing ring and is threaded for a TTS ER20 collect chuck.
Here is the rendering:
Attachment 345130
I put small O-rings between the Probe housing and Mount to allow for tightening the M4 screws to perform On Center Adjustment:
Attachment 345132
Here is the Probe assembled and installed:
Attachment 345134
Attachment 345136
Here it is next to my Wildhorse Probe (The MP3 probe is huge!):
Attachment 345138
Fusion 360 CAD/CAM Files if anyone wants:
MP3 Adapter-Fusion360
The repeatability is pretty amazing - measuring the same surface over and over was usually exactly the same - sometimes off by 0.0001 even with a crappy homemade stylus that isn't concentric (have a real M4 stylus on order).