Customizing for 2 Y axis motors

[JustinD]

Hi, I'm building a very large printer that will need two motors to drive the Y axis. I bought two NEMA 24 motors that should have the torque to move this machine. I also bought two external microstep drivers.

I'm using GEETECH RAMBO 1.2 boards to run the printer.

I'm thinking there must be a way to reroute the output of the Y functions away from the internal motor driver to a set of unused pins, and then to my external motor drivers which will run those two motors.

Does anyone have an idea how to implement this change in Marlin, and what pins could be used?

The other option would be to just find the right spots to access the pins coming off the Arduino chip going to the Y motor driver and solder wires to them to go to my motor controllers. Long term this isn't a good option though, since I'm hoping to sell these printers & I can't be customizing boards like that for mass production. Especially if people need to replace their boards in the future.