Help cutting an O ring grove

[mike-sid]

Well, I did the job before I red Ken's reply. I think I did OK. The tubes are made to drop in as is, but that was not good enough for me. The O-ring is just to hold the tubes snug to prevent the annoying rattle. Here are some pictures of the job. I first mocked up a section of the tube and put an O-ring on it to check for fit and final dimensions, since I kinda winged it.