Dan,
These look to be a custom job, specially made for the GT40's. See
www.racingicons.com, awesome site full of excellent photo references and text - and if you use Mozilla Firefox as your web browser (as you should be, Microsoft junk indeed [img]/ubbthreads/images/graemlins/smile.gif[/img]) you can right click and save the images.
Lynn - I concure with Dan, cannot find the 'L' shaped fasteners shown above - either that or I'm not looking where I should be...
Chris