In my opinion, leave the receiver as it is. Have the barrels reblacked if you need to. It sounds like it's a using gun and you don't want to be candy assing it all day. Re-case coloring is expensive because every moving thing has to be taken out of the receiver and forend. There are no guarantees it will work as well, if at all when it comes back. Sometimes things warp.Those guns were meant to be used.

[IMG]