A couple of months ago I posted a question on disassembly of the Victor Concert reproducer. In one of the responses somebody posted a drawing for a disassembly tool.
For my G&T New #3 project I needed a concert reproducer. Recently I came across one, but it definitely needed a rebuild.
I used a piece of brass bar stock and turned it down on my lathe. On the second picture you can see the tool and on the first one the tool with the outer ring inserted.
The tool worked very nicely, made the disassembly very easy.