Hi I bought a cncest 3 axis mach3 router but can not get to grips with mach3. I have decided to convert it to grbl and then thought why not have it with both controllers in it. Im thinking if I put another usb socket on the metal controller case I can connect that to an arduino uno grbl board and if I put a 2 position 7 way wafer switch I can switch the inputs to the dm542 drivers to either the mach3 or grbl boards. It has no limits or homeing switches so apart from a probe pin I think that is all I need to do and with no positive to the unused board I dont think it would hurt to link the probe socket to both boards to save amazing 2 probe sockets. There is one extra way on the wafer and that can switch the positive to either board so none of the boards are left switched on when not being used. Has anybody done this modification? Can anybody please give me their thoughts is it a bad thing to do for any reason? I just thought why buy another power supply, 3 x dm542 drivers an enclosure sockets and so on if for £15 i can buy the switch. Any links to this already being done would be good if you know of one but its such a simple modification I dont need to follow anybody else's work but would just be nice to see how they have gone about it.