What would I need to look at to determine if I need new plugs, I was told they were changed at the time I bought the truck- but it's starting to hesitate.

I haven't 'hooked it up' yet, but I imagine there would be some sort of diagnostics available to tell if COP(s) or plug(s) need replaced?

Any evidence to look for if they didn't do the plug change as promised?

Anyone know the old vs. new motocraft spark plug #s? (Dealership did it)