yep, i do that, but for some reason only on the planes i have open tanks on anyway LOL leave the carb line clear so you can see the fuel go though and any bubbles..
i also have the pressure line long, the fill one short and the carb just the right lenght, i also use a thinner tube for fill. so i rarely get confused.
theres lots of clunk reasons to cut... if its too short you run out of fuel too soon, if its bent over after heavy landing or if too long and bent over with vibration it'll mean you can draw fuel at idle but cant get enough though at full revs.
not saying you got this wrong.. but best clunk set up is about 1/16th inch away from the back of the tank when you hold it up, you should be able to shake it without it touching the bottom, but be close enough to see the end though the opace plastic.
make sure the brass tubes havent cut the lines on your tank, i also find the brass breaks, i had the fill pipes on my diamond dust snap a few weeks ago inside the tank, landed with nice rattle. ive also seen the clunk break up!