UPDATE:
After a few hours of denailing and scrubbing the blackened side, I am really excited at how good these boards are looking (see pics). The black soot mostly came off with some elbow grease and a steel brush - leaving a beautiful red stain. (maybe it was cotton oil after all? Or maybe it was cotton oil and something else). It looks so good I almost hesitate to plane it off, but I think I can achieve a similar look with tung oil/BLO if I want.
I am thinking for the lead side that I will just use a chemical stripper first and get as much as I can off first, because it is extremely flaky right now and I'm thinking the planing will cause a lot of debris/dust.
Suggestions and input are welcome.
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