My TR-3 is a 1960 by title and 1959 by serial number. The gas cap is the type that then has an escutcheon, goes down through body and below is a "fiber washer" then extention that goes into the rubber connector to the tank. TRF, Moss nor British Victoria have the fiber washer. Does any one know of a source? Or has anyone made one and out of what material? Thanks Tom