And I believe ACQ has been replaced itself, with something less corrosive, MCA. If he's doing a thorough job of finishing it with poly, it's unlikely to be an issue without direct contact. Plus if he uses stainless hardware, even the ACQ shouldn't be a problem for many, many years.

'69 1/2T stepside, Sea Foam Green, 250 L6 w/ 3 on the tree, not an option on it, in the family since new.