You gonna leave the wood bare or cover with carpet? Marine grade carpet will protect the boat from the PT chemicals. You could get a roll of the butyl tape used to cover the joists on a wooden deck and cover the bunk boards with it then carpet the bunks for extra protection and piece of mind. Or put the poly bunk slicks on them... just make sure you don't unhook the strap from the bow eye until the boat is in the water; heard bunch of stories about peoples boats sliding off the trailer. Just be sure to use SS or PT rated hardware.