What holds on '72 wiper blades?

["John Middlesworth" <top_down@worldnet.att.net>]

This is just to confirm what I suspect.  Victoria British sent me wiper blades
for my '72 MGB that are designed to be held on via a dimple on the top side of
the wiper arm.  My arms instead use two small notches on the side of the arm
to retain the blade.  I think my arms are original and I'm ready to send the
blades back to V-B.  Concur?

John Middlesworth