Originally Posted by
Grand Bois
I don't think you've thought that one through. Cutting out a small section would not allow the cup to be inserted.
Actually this approach looks promising. If you cut a slit through the fixed cup, you can probably thread it in. You can then apply force to expand this cup so the threads are protected.
Maybe another approach is to insert an aluminum sleeve (with a slit) that barely fits, then try to expand it to reshape the shell.