Well I finally gave up on the p-bottle and decided for the relief tube set up. No more loosing cap under the seat with a filled bottle, no runs to the FBO rest room to empty the bottle and the bladder, no more looking for a nice tree to hide. Now I can drink my Diet Soda in flight and no need to worry about. In fact my next project is to have cup holders. I bought the components from Aircraft Spruce for less than $50. Took me three hours to install it on my 82 M20J with multiple belly panel