The mechanism is essentially identical to the Seeburg select-a-matics from 1951-1955 with a few exceptions. When I am stumped, I refer to Ron Rich or one of his manuals. I think he is the best resource for this line of Seeburgs.
Just my .02
I found Ron to be helpful but at the same time not to patient with newbies! He promotes his book I bought it hoping for pictures etc. It was basically ALL text! Good info just not formatted for comprehension for ME!
The constant default was read the manual. Manuals are great but like our site here ask and you real really get very good information without the expectation to have read the manual!
The best video I found was of Mike Zuccaro he walks you through step by step with a Seeburg R. Video is very detailed great for a newbie into the hobby especially learning the machine!