NOW,,, someone needs to convert it to a TWO pedal foot control.
Once you use a hydro with separate pedals for forward and reverse,, you can not consider a one pedal.
Keep your heel on the floorboard, and simply swing your ankle between the pedals.
With a 1 pedal dual control,,, you are constantly holding your foot in the air.
From looking at this one, I think you would only need one more rotating shaft,, and a connecting link.