I understand that there is a book which covers the interchangeability of parts among different cars. Does anyone have this book? If you do, would you kindly let me know if the heat riser valve on a '49 Caddy interchange with one from a similar or later year Buick, Olds, or other GM car. I believe that the Caddy 331 CID engine was used in other GM cars in the following years. I've been looking for that heat riser valve for some time now. Any help would be appreciated.