dwcraig
How about a description of the added parts?
The top started out as an extra top assembly to a Segelei 8w
I had to sand down the height of the cap so the 510 connector on the MKB would reach the top of the 8w cap
I also had to file down the nubs on the 510 connector so the attys/tanks would seat properly in the connection.

I shortened the floating pin while I was at it. Gained another 3/16'' in shortness
The o-ring helps the cap from turning, the threads were not a perfect fit.
I also fiddled with the bottom switch post a bit. I had a problem with the mod firing without pushing the switch. I found that while using a 2cent fuse that the fuse would touch the switch button locking nut on the inside of the tube.
I found some brass hollow brass tubing, a brass bolt that was close to the inside diam. of the hollow brass tube, and a bit of shim stock.
You can see the steps in the switch tube. I added some nolex and pushed it down in the center of the switch post. This raised the fuse away from the switch nut.
Sorry the pic didnt post to my PB.