Once someone has decided that they have nothing to learn from those who have knowledge, they cannot be helped or taught. Do it how you want guys. The OP asked a question, I answered it with the correct answer. The photo corners I recommended are archival, cheap, easy to use, fully reversible, and acceptable to museums and galleries if he is fortunate enough to get shown by any.

As for dry mounting, 80 yrs as some mentioned for Adams work, is not really long. There really are good reasons NOT to use permanent adhesives.