I am new to PCP and may have a tendency to make a wrong decision because of a lack of knowledge of how the game is played. In an attempt to save some bucks, I purchased a Scott 4500 psi 30 minute SCBA tank. It has a fill valve with gauge and a male extension threaded for CGA347. Is there a PCP fill valve kit I can get so I can use this tank for filling and topping off my PCP airgun? Sure hope I didn't screw up on this decision.