3D printer extruder attachment

I want to add a 3D printer extruder to my LongMill.
This is so that I can make large mixed-material objects.

I think I could use the “Spindle PWM” port of the LongBoard controller to control extrusion of the filament.

Wondering if anyone here has attempted this or has any tips?

Were you wanting to use another stepper motor for the extruder?

I would attach an external driver board and then the stepper motor attached to a filament extruder.
I need to be able to control another axis in g-code on the LongBoard controller.
I hope I can configure the “Spindle PWM” port as another axis.
Or, are there any other connections I can make on the LongBoard controller to get one more axis?

Since there are only 4 motor drivers on the LongBoard - one being a y-slave - then you’d certainly need an additional external driver. It’s an interesting idea trying to use the spindle PWM to drive it, I’ve not given it much thought but it could be possible