Removing aluminum corrosion

[relative4]

I need to replace the timing cover on my Rover 3.5, and I have a spare that's been sitting around a long time.  It's never been used, but it has accumulated a bunch of aluminum oxide that needs to come off before I can use it.  Any recommendations on a good solution?  Hopefully a spray to get into all the nooks and crannies?

[ex-tyke]

Might try good 'ole vinegar for a start. Commercial aluminum cleaners are, I think, muriatic acid based.
Then there are the CLR products that might have a suitable solution.

Edit: If it were mine, I'd get it bead blasted.

[MGBV8]

I'm with Graham. Bead blast it.  I have a friend that used to spiff up his aluminum intake with Brillo pads.

[relative4]

I assumed bead blasting would compromise the mating surfaces.  Not so?

[ex-tyke]

If it's done properly, one can easily avoid blasting the side/mating surfaces.
 I've done a few front covers and intake manifolds without any issues.

[kstevusa]

JUST BLAST IT WITH NUTS!    shells :-)

[HealeyRick]

Aluminum deoxidizer: http://www.californiacustom.com/aluminum_deoxidizer.html and Purple Polish:   http://www.californiacustom.com/purple_metal_polish.html