Hi. I have a customer who wants to frame a oil on paper. I have previously hinge mounted the work. The client does not like that it is not totally adhered to backboard. She does not like the waves the paper makes. But, I have said that it can not be dry mounted, etc. etc. She is fine with me mounting it any way I can because it is her son's work, not going to be of monetary value. Is there some sort of spray or something I can use that will PERMANENTLY mount this pc without coming up at a later date. She does not want glass. It has to be a I hate these "tacky" situations!! thx. s.