ORIGINAL: Fred Hindle
Mark,
Cars of this age don't have securing nuts of any description. Plus the fact that the badge panel itself is welded onto the car, later cars these panels were secured on with screws. So you cant get to the underneath of the panel. The badge has two pins that are set slightly pointing in towards each other, this allows the badge to stay flat against the panel (with the rubber in between). By all means use Geoff's method of securing the badge and rubber together with superglue but just press it into position on the panel.
My 944 (1984) uses pins rather than securing nuts.
To remove, gently pry the badge up with a flat bladed screwdriver. This is the English 'gently pry' not the Haynes Manual meaning of the term - Haynes: Pry...
Translation: Hammer a screwdriver into...
Cheers,
Fred