So, I finally got the valve that comes with it off, saved the O-ring and put that on the nipple, but it won't fit. Every page I look at with instructions has the same size for these to put in your cooler. What should I do? It fits well without the O ring as far as width, but can't get both in and if I did it wouldn't be long enough. What to do>? Don't mean to ask stupid questions, but what is my next step if this is my scenario? I have a 10 gallon cooler.