I have used the Great Planes fueler in all my aircraft with NO problems. I dont know why people are having problems with them. It is a very simple setup and works great for enclosed engines. I would go with this route VS an fueling dot because a dot doesnt stop the flow to the carb like these fuelers do.

Good Luck, Phil (Mesa, AZ)

Used with an 0.S. 46 FX (NO PROBLEMS)
Used with an O.S. 70 Surpass II (NO PROBLEMS)
Used with an O.S. 1.20 Surpass III (NO PROBLEMS)
Used with an O.S. .91 Surpass II (NO PROBLEMS)