I suppose if you want to reduce stress on the wood, you might consider using a fairly large head diameter on your lock bolts. Would be more authentic styling, IMHO, than the small headed lock bolts ("side nails", to be persnickety) currently available.
Such large head size lock bolts may not be readily available.
I usued to make mine by buying a carrage bolt for its large head, hand cutting screw-driver slot with a hacksaw & files, filing off square stuff & hand-threading to fit.
Caustic soda/lye, or Drano, whichever Our Fine Government will allow you to buy currently, will dissolve remaining zinc galvanizing.