I think I solved the problem and will post pictures and come back and make comments.
Okay I'm back.
I grubbed around and did some measurements and found the SCH 40 inch PVC inside diameter is just about the same as the outside diameter of the back shoulder of the MG bottle.
So I cut and trimmed one of the bottles as you can see and epoxied it into a length of 1 inch PVC.
In the last pictuer there is a wee groove cut in the shoulder this may be for air inlet I dont know.
But is it is it wont matter because now you will be going to a tank and it can have it's own air inlet.
By connecting this pipe to the bottle top you can now connect it an any way you want to any kind of tank you want and not have to buy the expensive refill bottles.
even if the groove matters you can always file one up along side the pipe to accommodate it.
Worth
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