I used the rattle cans from LPE, but Duplicolor has the same stuff cheaper. I painted my plenum & I/H's back in October 05 and the stuff hasn't faded, cracked, flaked or done any thing unwanted. The plenum has been off a coupla times since also, and no flaking at the bolt holes either.
I used a low VOC aircraft paint remover, for use on thin aluminum so I guess it's not too caustic? Any way, scotch bright pads & small brass bristle brushes to help the remover, a wash down & dry and then a high heat primer & then the paint. Just don't make the mistake I made with the clear top coat....wait a few days for the color coat to dry. I was pressed for time and only waited about 10 hours....bad decision!

JMHO

Tom