Art,
The screen was tilted forward so all of the light from the tubes
was aimed directly at the viewers who were expected to be sitting down.
The screens were very highly reflective (and easily damaged) because
the tubes were not as bright (not liquid cooled) as todays projectors.
The screen was mounted onto the back of the projector on two large
metal arms.
I don't think you could converge it if the screen were wall
mounted unless the distance to the tubes was close to the same as the
original cabinet mounting. Used to work on those beauties and the
larger six foot KP-7200.

Ray
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