With all due respect to the desire to build something cool (I know that I succumb to it occasionally), this is one of those situations where you have to consider the best interests of the customer. In this case, there is a solution already commercially available that is designed to perform this exact task, and can be obtained for a price that is likely less than the cost of your raw materials. Have them take a look at the
Gigapan Imager. This device is used as the standard device by the
Gigapan Project for acquiring multi-billion pixel panorama images.
-dave
.