I have a couple of questions about how to do this:
Is it safe to cut the bottom 1-1.5 inches off the track so that it's not in direct contact with the concrete of the garage? I often get standing water during the winter up against the garage door and this would prevent the track from sitting in it.
Would regular rust proofing spray paint be adequate for this kind of use? I don't believe the portion I'm cleaning is actually in contact with the roller so it shouldn't get too much rubbing from the rollers.