You were told wrong, the rotors can be replaced without replacing the studs. The way I've done it is to remove the rotor along with the unit bearing and place it on two 2x4s with the bearing hanging below in-between the 2x4s. You can then drive the studs out with a soft hammer. I've had some that have been tough to get out, but just laid a piece of plate aluminum on top of the stud and wailed on it with a sledge hammer, one good hit is all it takes. Never had a stud I couldn't reuse. You could also use a press if one is available. When you go to replace the studs it's best to seat them down without the wheel in place, you could damage the rim, especially if it's aluminum. I use a few washers on each stud and pull them into place with a nut, that isn't a lug nut you are going to use, with an impact wrench.
Another warning is when you pull the rotor/bearing off the axle shaft make sure that you don't pull out the axle shaft, you can damage the seal inside the differential. Again sometimes it takes soft hammer hits to the end of the axle next to the rotor to get it to come apart where you want.
All of this is outlined in the Dodge service manual, too late for you now, but maybe next time !!!
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95' 25004X4,AT,Driftwood,Banks Stinger,Warn fender flairs and running boards(work truck)
95 3500,5 speed 3:54,BD E-brake,Driftwood,Banks&Psycotty,34,000 GCVW apple and tractor hauler(works harder truck)