yeah those round "top" looking filters just have a fine mesh screen in them, so those don't matter which way they go.
if you have an autozone near you, go there and get one of these style filters.
they're small (about an inch long), have a nice, real filter inside of them and they have an arrow showing the direction of flow. it's made to fit 1/4" i.d. fuel line...and they sell the line there as well. the bigger round end goes towards the carb and this is where all the crud is collected. the filter inside is narrower at the top than the bottom so the gas flows around the outside of the filter and then through the filter, and the crud can't get into the carb. the crud is collected outside of the filter and settles to the bottom. the good thing is that they are clear so you can see the build up of crud and you can also see if you have fuel flow. I run these filters with clear fuel line which allows me to see what's going on without pulling the fuel lines or filters off of my bikes.
these filters are easy to clean as well but they don't come apart. i just spray a little brake clean in the filter, turn it upside down and tap it on the ground and the crud falls right out. it's amazing how much crud can be filtered out of gas, even if you have a clean gas tank.
Part Number: 334283
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