Sounds remarkably like what I suggested in the 2nd post in this thread
I'm still of the opinion that the software is going to much more important than the hardware. I've seen some pretty poor examples of stitching by the Gigapan software with ghosting and misaligned features. You will need to review every blend line in the stitched image for accuracy and the software must allow you to edit the blends. I'd suggest trying PTAssembler, Microsoft ICE, and Autopano Pro to see which one works best for you.
Yep. I re-read your post. Just when I read what you wrote, I immediately focused on the your idea of a track system moving the artwork and dismissed it because that won't work shooting in a museum. Didn't think of dolly track until later.
The gigapan software becomes moot if I go with a track system, because I won't invest in the gigapan system.
Thanks for the stitch recommendations.