I have a model 36 (1968, verified by letter) that was a pass down to me. I've been carrying it in an open top Don Hume holster. With the hot summer this year excessive sweat has caused visible rust on the frame just above the left grip and in front of the cylinder latch.What is the safest way to remove this rust without hurting the bluing? Is there a good way to prevent future rust? Can I remove the cylinder latch to get at that rust without causing problems? Yes, I am new.