From what I have seen in the Veeder totalizers is that they are sealed with flared stud ends.
There are no nuts or screws that can be removed. Keep in mind this is Veeder, Not Veeder-Root.
Similar designs/ideas in the parts, but still different.
What I have to do on several computer parts is to grind off (or drill)the top of the stud flare, being carefull not to hit the metal it is holding.
After the parts are separated, I use a drill bit to bevel the hole. Then there is just enough of the original stud to flare back into the bevel.
This can be done on thin metal, like in the pic. I use a ball peen hammer and punches.
The pin on the end of the blinder was moved so the blinder could be modified to fit an older computer.
This may be what you have to do to get the unit apart and to re-assemble