replacing upper control arm
The end of the A body run was 1976. When I pull them up in Hollander Interchange there isn't a difference shown between drum and disc on the 1973 up. Over the years you never know what has been changed as we see on this site all the time.
Here is a good thread that is worth reading on this subject.
http://www.forabodiesonly.com/mopar/showthread.php?t=224207