Office layout plan directory

Just a open question aboout best way to do this I have moved to a new office 5 storey building around 400 staff the task is to create a simple directory that is tied to our phone list say BIGAL xxxx 5-A1 means ph extension xxxx 5th floor postion on grid A-1

Elsewhere a plan was produced which had a staff photo on desk position and a phone list on the side you still had to scan entire plan to find staff member. My idea is to automatically insert a image to a phone number position ie a block with image having the phone number as filename. This dwg already exists.

Its all pretty easy to do any suggested problems with 400 images xrefed ?

Or does anyone have a better idea maybe excel link ?