I have a stock 70 bronco, when i fill the tanks up and even if i dont top them off gas will run out and down the fender killing the paint. It is really weird.. some times it will not happen the day i fill up but a few days later.. I will walk out to the garage and there it is gas everywhere. what is causing this and what can i do to stop it. besides only filling up half way. the aux. tank has no venting and never did.. the main has a vent hose that runs up to just below the fill cap but both have gas running out the fill cap and down the fender.. :wacko: and the 70 did not come with evap tanks ..