I also recently installed the Cleaveland ports in my 14 tailcone with no issues. I used Proseal to glue them in. Follow the directions so you don't put adhesive on the inner flange which needs to be flush against the inside surface of the skin to make the vent (which is shaped exactly like Van's pop rivet) protrude the correct amount on the outside of the skin.
I had a Safeair kit on my RV-8A and the airspeed was 5-6 kts low due to the static system error, so I'm hoping the Cleaveland vents perform better. Also I think you can buy just the vents or the whole static system kit including nice quick disconnect fittings. I think it's a great system and given the price point of the -14 (and the fact that most are equipped for IFR) I wish Vans would just include the Cleaveland system with the kit and save us all the hassle...
Spring Hill, KS
RV-8A N2D #80583 - built/flew/sold
RV-14A #140017 - wings complete, empacone in progress...