Hustle on down to your local auto paint supplier store....the really big one where all the shops have accounts. Sally on up to the counter and tell the nice lady/gent that you are about to embark on an aluminum painting adventure and would like a list of the products you will need in the appropriate quantities. Take a tablet and pen or the money to make the purchase.
And yes, before you ask, "Holy crap!", it is all needed.
The pay off for neglecting this process is that you get blisters popping up all over the painted aluminum anywhere from 30 days later to 2 years hence.
TWH(this will help),