I have had Dupont Automotive urethane with a hardener on my huckster bed for almost 10 years. The automotive clear is bulletproof and has outlasted the best spar varnishes and urethanes I have seen.
Bruce Horkey tipped me off on how to do this when he was starting to get going on bedwood...again about 10 years ago.
No cracking checking or peeling when done right. There are some limitations but overall this is absolutely the way to for the truck that wants the perfect bedwood look.
Think about the flexible surfaces that we put clear coat on now in today's vehicles: bumper covers, mouldings, etc. It's very flexible and UV resistant.
