it's really hard to explain the exact issue.
i'm referring the open to floater and fuel pump.
lid to be mounted to tank with bolts.
lid seal is there.
but due to some reason (can not understand how this happened) surface where we are to fix the lid is not even.
hence though we fully tighten the lid, there is a gap between tank and lid at some places.
since the nuts seems to be welded to tank, this seems to be a bit advance tinkering work to repair the surface.