Help 70-72 Duster owners

It is a washer looking clip. I'm not sure what it's called but it is like a round washer with cuts on the inside and it is pressed on the pivot shaft. I put mine by putting a socket over it and hitting it with a hammer.

This is the part..RETAINER PUSH ON 5/16 STUD
www.rtspecialties.net
has them for 50 cents