Or better yet, bite the bullet and pick up a set of front rotors to go with those new pads. Making front rotors thinner on a 6,000 pound vehicle by cutting them down is iffy at best. If you don't have a brake pulsation right now, you probably will develop one after slicing up your rotors.
Replacing pads and rotors together as a set is the best way to do it.
While I agree it's the best, the rotors are designed to have enough thickness to be resurfaced before you get below the minimal thickness-as long as you don't cross this, your ok. Whatever you do, you need a clean surface for the new pads to deposit some material onto the rotor evenly. The pulsation is caused from uneven material transfer which causes bumps or hills and valleys of pad material-this translates into vibration when braking.