I actually watched this exact video earlier today and another guy working on a 5 valve 4.2. It’s much simpler than I thought. Lock timing in place, remove cam, pressurize cylinder, compress spring, remove retainers, and gently as hell replace the seals. Hopefully there’s a shop around that can do this. Got to it it back together first.
Is it possible to release the chain tension on the cam adjusters without having to remove the main timing cover and therefore the engine?