I just sucessfully removed the rust from the backstrap of a police carried model 58 . The backstap was the worst part, being exposed while on duty.
On another revolver the steel wool / oil was too. aggressive and got down to bare steel before before removing all the rust. The secret...Turtle Wax Chrome Polish and Rust Remover. I saturated small patches and rubbed the area until the patch was brown, then got another patch, saturated and rubbed again...when the patches stopped turning brown the rust was removed and any finish was left. It doesn't put a new blue job on but it will leave any color/patina that remains. I used it all over the metal parts and it did a wonderful job cleaning, removing rust and polishing.
I like the Turtle Wax method a lot better than the steel wool/oil method.
gary