I dont see what the big fuss is. To me, all he has to do is bend the
tabs back in or down on the "flange" or "cage" that holds the HU in the
dash, If you look closely at pic 2 and 3, there is a little indent
which looks like something may be holding onto the HU. Maybe a small
flathead screwdriver get in there and wiggle and twist than push the
two tabs in on the sides and pull out radio leaving the cage where it
is. Unless there is some metal bracket on the back of the HU through
the glove box that Mike said, but ehhhh, I wouldnt think so.
Thats how mine works. Since theft isnt a problem where I live, I never
pushed in flange tabs so it slides out easy.