Ok I was thinking it was wrong but I think I will go with better fuel line and some clamps before I put back together , thanksIt's backwards but that wouldn't make it leak. The reason it mounts the other way is you want the incoming fuel to flow from the outside of the paper element to the inside. That way you can see when it's dirty.
pretty sure it's leaking from the line , I very carefull not to tighten the tank down to much , from what I have read that's happens a lot , thanks for the adviceIts hard to see, but there is a faint arrow outline on the side of the filter that shows the flow direction. Like Spare_parts stated, you want it the other way or else you won't be able to see it getting dirty. Being strictly gravity fed, and having oily 2stroke mix, a dirty fuel filter can starve your carb pretty quickly.
Your leak is likely (hopefully) coming from the thin rubber gasket on the petcock, but if you overtightened the gas tank brackets you may have a cracked at the base of a stud mount.