You can polish the aluminium, but I think the natural "tone" of Aluminium will still be different from Zinc. You could maybe electroplate the aluminium with Zinc, but that might prove difficult. (Nothing wasn't to plate onto Al2O3 (Aluminum Oxide) very easily, and Aluminium naturally oxidizes pretty rapidly when exposed to Oxygen, so you'd have to polish off the Al2O3 in an Oxygen-free atmosphere (Probably N2 would be easiest, or under water) and also electroplate it there.)
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Short version:
if you polish the Aluminum, it won't be the same color as the zinc.
There's a process to plate zinc onto the aluminium (To make them match), but it'd be really hard.