I thought about this too, I was thinking about mounting one right side up(below the image on a stand) and the other one upside down on the ceiling (above the image) that way you could get the convergence right.
The only other way I could think of would be to use a rear projection screen with one unit behind it and one in front matching the images. I think I am going to try this, think 2200 ft lamberts for $2000!!! how big of an image could I throw?!
If this will help reduce rainbows (which in theory, it would), then it could be a worthwhile effort. Widescreen review uses a set of stacked single chip Runco's in one of their theaters, so I certainly think that there is some merit to trying it. Go for it! And let us know how it works
BTW, there is a thread in the >$5K forum about this as well...
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