Hi MF,
I would go over the whole lot with 120 grit paper and then finish off with some 400.
Then I'd prime the whole lot with a good etch primer as you are dealing with Ally here. As far as wax and grease remover is concerned I always use Prepsol or equivalent just prior to painting.
After priming I rub back using wet 800 grit but make sure you have a good coverage of primer so you don't go through it when rubbing back.
From there you're ready for a good well shook up can of Ultra Color Hammertone Green.
Give it a light coat of green and let it flash off for a couple of minutes and then hit it with a wet coat, but not too heavy otherwise you'll end up with runs on the vertical areas. Try and keep the surface as horizontal as possible as this way you'll get a good finish without any runs.
I must admit I ran all my parts through the oven once they were able to be handled well enough without finger marking them.
In saying the above you probably won't be able to bake a whole chassis so it will have to remain out in the sun for a few days. One thing I have found though with this paint is that even though it might feel dry to handle it will still be soft deeper within the paint, so don't be in any rush to do the fit out of parts for at least a week if not more. I've found that I sat my clutch body on it's engine side downwards on my bench for a few days only to move it yesterday to find that I had an impression of the timber surface of the bench pushed into the paint. Luckily it's the surface that you won't see as it's against the engine once the component is bolt up.
Cheers,
BB.
