Okay, so I took a picture. Not the clearest picture, but it will work for describing what I would like to do.
From top
1: A 901 atty that I gutted
2: 510 to 901 adapter
3: Center post for the 510 to 901 adapter
4: Bottom post for the 901 atty I gutted
I figured I could drill a few holes in the middle of 3: and a few holes in the center of 2: to get the adapter to work for Kr Cartomizers. I cant drill a hole in the threading of the 510 - 901 adapter because of the rubber that would block the airflow.
I already have a 901 -> cartomizer adapter and it works with my 510->901 adapter, but the length of the two adapters together leaves much to be desired.