"Gig 601XL Builder" wrDOTgiaconaATsuddenlink.net wrote:
FAA MAY TAKE AWAY PANEL-MOUNT OPTION FOR PORTABLE GPS
Think your portable GPS would work great mounted to your old Cessna
172's instrument panel? If the FAA has its way, you won't be able to
mount it.

Here's the proposed rule changes (section 21.9 is on page 31 of the 40 page
PDF document):

http://dmses.dot.gov/docimages/p87/416626.pdf