Hello gents, for the record, the TVS series of tecumseh engines do not use a spacer ring, the early sideways mounted briggs also do not have a spacer ring, both these models are short shaft engines (35mm approx) and will not fit on many other decks, especially the rover and Masports, the blades will be too high up in the pan.
The later model forward facing briggs have a 50mm shaft length and use the spacer ring, Rovers, Masports etc use the more common long shaft motor(75mm approx).
So the short story is you need 2 victa powertorque style decks.
Cheers, Ted