Heres my situation, I recently bought a CNCEST 6090 machine.  The controller box that came with it does not have a port for a laser hook up or a Z probe.  I do not want to void my warranty or possibly damage my unit so I don't want to open it to access the internals.  So I bought a cheap 2nd Grbl controller on amazon that has a laser and Z probe connector.  I also bought a USB splitter and ran it to both controllers.  How can I get Mach3 to run my XYZ and Spindle off of the CNCEST controller, and my Z probe and laser off the other controller?  The CNCEST controller runs the axis and spindle motors just fine, I just want to add the laser and Z probe without having to open the box.  Basically I just want Mach3 to view both controllers as 1.  Any help would be great!