Thanks for trying guys. I know I've seen one out there somewhere on a vintage style motorcycle.
Approximately 18 to 24 inches long and about as wide as the turnicators. Mounts above the rear fender like a luggage rack. Perhaps 8 or 10 inches deep with a vaulted (domed) lid, hinged along one side. Made from a nice wood and well varnished.
I just can't remember if what I have seen is a picture of a new made item or if it was something from the 30's or 40's used to deliver parcels or groceries.
Well, it doesn't really matter as I have a good idea of what I want and now I will have to make it happen.
Thanks for your efforts.