Put in some new spark plugs, make sure you have good brakes, and drive the truck. After a short time, pull the plugs and see if they tell you anything.
Its too soon to start tearing the engine apart.
You can spend a lot of time diagnosing everything, but if it idles smoothly and accelerates properly, there is no reason not to drive it. These engines like to run. Let it.
Your diagnosis of problems will be more productive after you run the engine for a while to get the "cobwebs" out
Carl
