Baronfoxx, there have been several articles written in various publications ( can't remember the exact ones) that warn against using spray mounting adhesives on fiberbase papers. It seems that these adhesives are O.K. for short term display of RC papers, but they are not suitable for long term archival mounting, especially with FB papers. For many years, I dry mounted my FB prints (in a heated press). A few years ago, I read an article written by a person that I trust and respect. He explained that there was evidence that applying heat to toned FB prints caused changes in the tonal coloration. That was all I needed to hear. I frequently use warm tone papers and Selenium toner. I sold my dry mount press (it was very old, heavy to move around, and ugly to look at). I now use acid-free double-backed tape, from Light Impressions, to hold my prints onto the mounting board. Then mat and frame them. Just a small square of tape at each corned does the trick. I can easily remove the print from the board, if need be, and I avoid heating my prints in a press.