Marushin Mossberg with external air?

[bean]

So I will admit i have a soft spot for the classics. There the guns that got me into the game all those years ago. With my latest toy I got to thinking after seeing another mod guide. I was looking at classic airsoft and noticed a guide to turn an m1100 into a gun with an external rig. However that gun is set up differently then the m500. It has hoses inside whereas i dont think the m500 does. The only forseeable way i can see of doing this is removing the fill valve and replacing it with a quick release hose adaptor and hooking it up to a palmers rig. Now my question to those who know far more then me about gas fittings. How hard would it be to jerry rig a quick release hose fitting?