Everybody knows I am not one to WIMP OUT, so if you do have the art I would be willing to take a look at it. Just keep in mind that for that picture we are doing (the guitar one) the file is 1 GB in size.
Needless to say though anything is possible. 
Yeah, but I have my pictures that I shot with my point and shoot digital....

Glenn, here's something to consider and avoid the headache:
Offer naked panels with no covering and let those that want to source
their own coverings do so.
That way you don't enter into these arguments/discussions.
That's what I'd do if I ran the circus.