I just tried a technique that a friend found on the internet about taking rust off things like manifolds and metal parts that you dont want to blast for the potential of removing "more than the rust." Its called electrolysis and consists of running a current through water and baking soda. It takes about 48 hours and it works EXCELLENT. Instructions for it can be found online.
NOTE: PLEASE DONT GO AND TRY RUNNING CURRENT THROUGH WATER WITHOUT LOOKING FOR THE INSTRUCTIONS! haha
