Another point - -
Search the earlier threads. The original sight-glass had issues. Many of us changed the design by closing the window ( after inspection ), and adding a Moeller Marine Fuel Gauge on top in front. You can see it in flight, and while filling, serious advantages. You will need some experience working with the 'gooo' then anyway, so you might as well build it yourself also. If the factory one leaks at any point in time, are you going to try to send it back ? ( don't think so ) !. My opinions.
John Bender