Polishing aluminum

[Ian Kerr <ikerr@domain.elided>]

Italian car people,

I am taking the heads off of a Mazerati V-6, and would like to take the
opportunity to polish parts up. Does anyone have a favorite method for
a.) cleaning grime off all kinds of aluminum
b.) polishing smooth aluminum castings
c.) cleaning bumpy aluminum castings or even polishing them somehow
d.) - a pipe-dream, I'm sure, keeping these shiny things shiny while in use.

I intend to use this car (a Citroen SM) daily but this seems like an
opportune moment to polish things up.

I don't have as much time as I would like, so I'm open to quick methods too.

thanks always,

-Ian