I've used the Super Duty Rubbing Compound and the Finesse-It II. Not sure that you really need the intermediate step.
My 'weapon' is a Bosch random orbital sander with the hook pad. I have a sponge pad for it with the loop backing (Bosch #RS013) for the rubbing compound and a buffing pad (Bosch #RS014) for the Finesse-It that work well. I dilute the compounds as needed, and use a restaurant type ketsup bottle for squirting the stuff on.
Hope this helps..