Ok, I didn't actually see the seals or know what they were for until I was searching the net after, I had only noticed the o rings and used them, I did roll them down the tube but I used some soapy water so they wouldn't pinch, I suppose I could pre fill the bowls with fuel thru the vent tube then tilt the carb back and forth to look for leaks? Failing that, remove and install the other seals.