[Mgs] MGB Visor and windshield center rod rivets

[John Elwood]

I took off the top rail of the windshield to replace those little rubber
blocks that keep the visor in place. (didn't want to drill through the glass
accidentally or have the drill slip).  The rivets are not like what I'm
familiar with...  Usually there is room behind the rivet for the end to
mushroom when the center stalk is pulled through.  These rivets are pretty
much flush from behind because the windshield gasket is right there.   Is
there a special name for this type of rivet?