How do I remove rust from vintage pedal?

[rocks]

I was lucky enough to get my hands on a very collectible pedal. It is a Mosrite Fuzzrite made in California, a very highly sought after fuzz pedal. The problem is there is some surface rust and I want to remove it without taking off the paint. The case looks like brushed aluminum, but it is steel. The paint I am trying to avoid removing is the lettering with the name, input/output, etc. Any help would be greatly appreciated.

[PRR]

http://www.vintagebmx.com/community/index.php?showtopic=4004702