Chrome mirrors only fit the '94-'97 trucks. '98 & up came with black power, heated mirrors. There is a set in the classifieds for $100. That's the best price I've seen yet. (Technically, they will fit but the harness won't plug in. )
To check, remove the screw on your inner door panel near where the mirror is attached. Look for the harness (you might have to pop a few clips loose from the door). I think the harness will be there, especially if it is a SLT.