What is not really clear is what the linkage to the powder measure is. The index rod does have the flat shell plate driver and the connector at the other end. There is another rod that may be the link to the powder measure. I have the Uniflow powder measure that I bought in '66. Looks like it should work since it isn't that much older than the press. Could that be correct?
Having never seen one up close I can't help you much, but I do understand that a definite weakness in the press was the old case-activated powder measure mechanism. On the later Pro 2000, RCBS copied Hornady's case-activated linkage which works like a dream. If I had a 4X4 with a Uniflow I'd buy the RCBS linkage Kit
and add RCBS's new powder through expanders
for each of my pistol calibers. Such would surely make your life much easier. Good luck with the machine.