Hi Mike
I always use Aluma Blast on freshly blasted cast aluminium as its the closest match i could get to make it look original.
I then finish off with Eastwood diamond Satin Clear lacquer.
Before painting i usually outgas the aluminium in the oven for 10 mins but this is not necessary, Its just for my piece of mind
A few customers parts below fully restored.
Hope this helps and gives yo an idea of the finish it produces.
Cheers
Chris @ PRP