OK, so I also decided to get the mounting templates to see if this might settle this. The upper and lower bars on the drawings match the actual louver bars on the Corvex ones, but the stud holes on the drawing don't match the actual louver studs. They are off as much as 3/16". That's more than enough to affect the alignment, I wouldn't know which holes to elongate to allow the louver to install properly on the quarters.
I don't know which is wrong, the templates, the louvers, or both! I think I will return both and regroup here.
BTW, I did a Google image search and came up empty there too.