Sony Vidimagic FP-62 geometry adjustment?
 

Hello, everyone. I recently picked up one of these rare projectors, with the Indextron tube. Powering it up, the screen comes up nicely, and I'm able to set the focus (at least within a fairly short distance; using a 50x50 screen, so I have to keep it within 6' or so of the projector), but the image projected on said screen (using a Jakks Pacific "Ms. Pac-Man" TV game as a quick 'n' dirty video source) is very much trapezoidal, much wider at the top than the bottom. I'm under the impression that the FP-62 included some sort of curved, aluminized screen, but mine didn't come with that. The screen I'm using is a standard glass-beaded type normally used with film projectors. Can the projector be adjusted to give a straight-sided picture on one of these? I have the projector sitting on a table roughly level with the bottom of the screen I'm using. Thanks in advance!
-Adam