Engine brush paint?

[Decoke Dave]

  I know about the Simoniz engine aluminium enamel spray paint, but is there any good match brush paint?  With the headers off I have  removed all the grease with good old gunk and cleaned the front of my engine and it's not too bad as the bike only has 11,000 miles on it.  I don't want to remove the engine for obvious reasons. Been told you can use a sponge type brush too good effect by dabbing it on the slightly rough cast finish at the front.  Any ideas.