Thanks. I have a dry mount press but the 3' width presents a problem. I'm afraid the 18" depth of my press wouldn't allow me to overlap the mount bites adequately.I would mount it onto gator board. If you have a dry mount press or a mechanical press or a roller press, the mounting should be straight forward.
Spray adhesives are not permanent, but they are toxic. Long after the adhesive fails, its particulate residue would still be in your lungs. Unless, of course, you use a proper mask. Spray adhesives are expensive, too.I know what you mean. There is also the option of using a spray adhesive such as Super 77 but that’s tricky to do and I am not sure how permanent it is.