What do you mean "no wiggle room"?I loved my old propane setup with my 15 gal SS Brewtech Kettle! The ball lock never leaked for me, and I also very rarely took it apart.
That being said, like @MaxStout said, tighten well, but not to the point where you're cranking it down with no wiggle room.
No. Meaning don't crank it down so tightly that you split the white o ring.What do you mean "no wiggle room"?
Is the ball valve supposed to be flexible?