If you have a rattle from your gearshifter you can remedy that by pumping grease down it. You will need to make an adapter with 1/2 20 threads on one end and a grease zerk on the other. Use hot glue to fill the holes where the reverse lock out is Then pump away , remove the glue and activate the lock out to get that grease really moving and repeat if you wish.
It also lubricates the spring loaded pads that hold tension on the lever Remove the adapter and replace the gear knob or leave it on as a custom job !