Jonathan
Thanks; although I'm not sure how much "progress I'm gonna make on this one... 
Bob2
There is 2 11/16" between where the (2) screws pass through the base plate, up through the frame and into the mounting brackets. The front hole is where the worm end of the bracket is tightened; the rear hole is for the screw that holds down the motor end. I don't see any way to adjust any of that...and theoretically, I shouldn't have to, right? My other example (with a slightly larger 1" motor) worked as designed...and those (2) holes are in exactly the same place.
I actually tried to move the lower bracket back up against the motor (like in my other one), but then the holes didn't line up for the rear mounting screw to pass through the base plate and up into the bracket.
In spite of the fact that these models can run really well (as my other example does), I'm not a big fan of the way these things were designed, what with the very rigid motor/bracket/coupling. There's no "play" in any of it, so you're kinda stuck with how it's laid out; unless I'm missing something...and I'm all ears... 
Mark in Oregon
PS: there's currently an example on eBay and it's had a can motor installed. If someone on this Forum buys it, I would LOVE to see how that was done...
