On my 1952 model the saddle measures 13.5" from back to front, the support springs are on 8.75" centres and the front mounting bolt centre line is 11.5" from a line connecting the support springs. It fits in the tank cut out. The front crossbolt is, however, attached to the saddle metalwork using two extension plates, one fitting on either side of the frame mounted boss just behind the tank. I am trying to work out how to attach a picture.