Your description is "text book" mate, but in truth, you can do it a lot easier. First off, degreaser is your friend, so buy lots of cans of solvent (not acid) based degreaser, (or Turpentine, it's great, but more expensive) and a range of cheap paint brushes so you can all the goop out of all the nooks and crannies.
Once you've degreased it, get a 3M nylon scouring pad (I steal mine from the kitchen cupboard under the sink, I don't know how they get there, but there's always a plentiful supply there, just use a new one, not a greasy one) and rub it over everything you want to paint to provide a "key" for the new paint, and to remove any oxidation. if you need to remove a section of old paint, use some "wet and dry" sandpaper with water, but if the old finish is OK, just use the scouring pads.
Use some Prepwash (not thinners, acetone etc, they're too aggressive, and might "lift" or bubble the old paint underneath) to remove any greasy fingerprints, wipe it dry, then hit it with a light coat of etch primer (etch primer is needed to bond paint to aluminum, so it's important that any bare metal areas are lightly covered. Let the etch primer dry for an hour or so and then hit it with the engine paint, using light coats with 20 minutes "flash off" time between coats to build it up to a nice deep finish, without lots of runs or sags.
Let it all dry for a couple of days before you start it for the first time, and make sure you don't spill any solvents on it, like gas, for instance. When you do fire your engine up for the first time, start it and run it for a few minutes until it's at operating temperature, then shut it down and let it sit for an hour or so, so the new paint can "bake" onto the engine. Do this a couple of times if you like, the harder the paint is before you subject it to road grit, stones, road salt, bugs etc, the more chance you'll have of it still looking good in years to come. Cheers, Terry.