John-looks like you`ve stumped us! I`m messing about at the moment with back m/guards and stays.Mine is the later type i.e. arrowheads with the correct later guard.I don`t have an earlier guard to compare but i have seen bikes out and about with arrowheads and the earlier mudguard,( given away by the small flats in the beading meant to clear the EARLIER stays) The stays will obviously fit straight onto the frame, leaving a redundant hole in the earlier mudguard that you could simply grommet off.The question is whether the hole at the rear end of the guard lines up with the late stay- you can always re-drill/ fill existing hole if needs be.Best of luck, bob.