[MEvang]

You say you have the pulsation problem, but you've given no history. You didn't know the upgrade had been done so I will have to assume you bought the truck and then the pulsation developed?
What I'm getting at is you don't need to be real concerned if you don't know all the history. What is the rotor thickness now? These rotors could have been turned a few times. Is there any rust build up on the hub surface? Of course you don't know yet, but rust jacking can cause runout. When was the last time the rears where adjusted? The rears out can put extra strain on the fronts. What brand of pads are on these now? Some pad formulas can cause problems with the rotors that can lead to runout problems. What are your driving habits? Do you tow? Drive hard and brake hard? Then this can lead to pulsation problems depending on the pad formula. Last but not lest are the wheels always torque when installed? This is one of the leading causes of rotor problem.
So if you change the rotors clean the hubs good and torque the wheel you should be good to go. My only concern is your choice of pads.
Mike