you'll probably end up spending a lot more making yours into a road bike than if you were to get a used 80's road bike and fix it up... and then you could keep the off road functionality of your MTB intact.
however if you don't want two bikes, i think you'll be spending at least $200 on new wheelsets and droptubes or brakes or tires... and your bike will still be pretty heavy after all that money.
is the 02 4500 a 26" bike? there really aren't too many 26" wheelsets available anymore.
however if you're wanting a bike from this decade, you'll have to spend a few hundred anyway so it's up to you.
in general, you'll get a far more rigid, fast, and comfortable road bike using a road frame. what kind of budget would you have for the project?