hi , anytime you mount an engine inverted ,get a pair of hemostats. you'll need them. the fuel always leaks into the carb. had a tai -ji pattern plane the same way. clamp the fuel line off. also they have permenent fuel shut off clips that stay right on the fuel line. they cost about 1.99 at tower hobbies or LHS. these are plastic and just need to pinch them on or off. a real time saver ,not to mention engine saver. you can route the fuel line on the outside of the cowl if you have one ,and put it there.................... worked for me...........RON