I'm not sure if you still looking for a way to make any and almost all of Matt's amazing pipes look churchwarden-esque haven't been able to read all of the posts, but I read over 5000 of them last night. Anyway, the Jack the Gripper 510-510 extension on EmpireMods should do the trick for your black stems. Was thinkin maybe leave the carto inside the eGo cone so there's no brass ring in the middle though. Just a thought.