u'll probably find one of the mouting lugs has snapped off (very common) i mad e anew ally bracked and revitted that into teh bottle with some epoxy resin underneath to seal the holes, you will find that in teh std location, one of the lugs is under a lot of strain (the one that snaps) I HAD TO ADD A SPACER (ABOUT 1/2") between teh lug and the shell to get it to sit nicely.