A quick warning if you should choose to use Simple Green or any of the purple (lye based) degreasers; The WILL attack any aluminum that it gets on. In the case of Simple Green, is may only discolor it a bit, if you wash if off fairly quick, no problems should occur. With the purple cleaners, unless you dilute them first, they will eat into aluminum in very little time. If you use it full strength, apply, scrub, then rinse off at least twice as quickly as possible, especially on aluminum. I have personally witnessed aluminum parts get completely dissolved in purple degreaser, sometimes in as little as 15 minutes. In addition, rubber gloves are mandatory when using any of the purple cleaners, it will eat your skin, even if it's diluted.
