[rotorwrench]

Wood should be preserved with something. I'm not sure what Ford used but I would doubt if they ever stained anything other than maybe wood that would be visible. Where it can't be seen, it just needs any form of paint or varnish that will act as a preservative. DP 90 was great for epoxy primer but I don't think is is available anymore. Any form of epoxy prime or even spar varnish would work. Linseed oil oil takes too long to dry and the smell is there for a long time.

I would just use bolts to attach as original. The head of a carriage bolt it too large in diameter for an easy counter bore plus I don't know how the square part would hold it for tightening the nut. That just depends on how hard the wood is. On a 68C a person has to have some good bolts to secure the lower top iron pivot brackets. It will have to be able to structurally take the forces acting on.