Glad to help Issac! I think they can figure out what I'm trying to do, they may need to make the center tit a bit smaller, but with the carto's I measured on hand, that .360" dimension should be mighty close!
I like the idea of the screw on tank as well, I know here it would be very expensive, but no idea what it would cost over there! I also would try and incorporate an o-ring in there as well just to keep the seal tight and not have the Vivi problem!
I LOVE your tank man! This thing looks really good, I mean REALLY good for the money! But I have to say I'm missing the 801's, not the look, but there is just something about them that is SO much better than the 510 fusion's! The 510's have been better than the others I've tried by miles mind you, they just don't seem to have the hit and the flavor I got spoiled on with the 801's.