Dual Extruder Help

Hello! Im working on a project to combine two filaments using this script: https://github.com/Gyrobot/Gcode-Filament-Mixer. Basically, it scans the g-code file for the tool changes and replaces the corresponding extrusion values (E) with with two different ones each representing its own extruder. I am having a hard time identifying what “E” (A and B) values the Taz uses to identify the different extrduders. Is this something I will have to modify in the firmware? If so, how would I go about getting that done? Thank you for your help!

I am not familiar with the filament mixer you referenced, but the gcode used to switch extruders on the TAZ 6, assuming the dual extruder firmware, is:

to select first extruder:
to select second extruder:

After an extruder is selected, “E” is used inside a G command to move the previously selected extruder motor.

G92 E0
does not move the extruder, but sets its current position to be the 0 point.
G1 E10 F100
will move the currently selected extruder to push 10mm of filament.

I’m relatively new to this, so if any of above turns out to be wrong, please let me know.