gear reductions?

[Mustang46555]

I've used a park flyer style rear reduction between the motor and gearbox with some success. It gives a 4:1 reduction depending on pinion, possibly more if you can find larger pinions. It is long which limits where you can use it. I've had good luck in a stock King Hauler cab. It gets close to the grill but clears. Rather than low profile servos, consider spacers under the front transmission mount. it will lift the motor up enough to clear a standard Futaba servo.