I found some listings for that motor part number calling a standard motor and others calling it a speed motor, so I don't know what it is.
But it is what it is and it seems to move the cart along nicely.
I must have guessed wrong on the make and model of both the old and the new tires, so now the taller tires explain the increased speed, but not the increased torque.
I don't have series cart to look at, but was under the impression the controller cover came off without mess with the F/R switch and cover.
Can you post a pictures showing that area.