Quote Originally Posted by Innuendo View Post
Isn't the centre hole for a bolt/screw that comes from under the dash that gets covered in mastic?
You can see that threaded-rod/bolt in the picture if you open it up and squint closer. Always shook my head at that, must have been an Engineering add-on required for some reason - you can't imagine GMH doing it from scratch that way. It may be a hangover from the original US designs for the HQ? The other guys have nailed the reason for the holes.