I think I'll just put a Benchmark cradle extender on a ring mount for the female Stab then. I may use a Shocktech drop, or possibly a CP Microdrop.
If it doesn't fit couldn't you just put the clamp around the neck of your tank and have the reg in front?
I also wondered that. If anyone knows if that'd work, let me know. It looks like the tank reg gets thicker at one point, maybe thick enough for the DZ 2.