If you try the oven cleaner be sure to use cold oven cleaner and DO NOT allow it to contact raw aluminum. Dampened rags on cold pipes work as well. The best thing I've found is S-100 polishing soap, this stuff makes chrome pop like nothing else on the market. It works well on pretty much any metal.
As a side note Speedy's All Metal Polish is the best I've seen to keep aluminum looking good with a minimal amount of effort. It's hard to find though, best bet is truck stops or truck parts stores.
