Hi Vince, I'm there NOW! '1903'/ HS GrubeeG4 and I'm making the tank mount from Black Walnut. Should be done within the week. Over on motoredbikes.com in the picture gallery section there's a gorgeous Felt 'Red Baron' by 'Give me V-tec'. His more recent pics show a tank mounted on metal hardware behind the seat that might give you some ideas. His earlier pics show a tank mounted on a rear carrier. BTW, I got my 1.25 qt. tank from small engine warehouse.com here in Muncie. Hope this helps.