It's an '87. It will need the work if you are at all planning to keep the car. The guides are of an older type of material that did not wear well. If you have the head off (the biggest chunk of labor)and you want to protect your investment give this work careful consideration. All of this depends on a number of factors, mileage, compression, any burning of oil (hard to tell with your current problem). Take a look at the plugs. Bottom line, do it now while you already have it apart, or...come back later and do it then.. Pick your poison..
2000 Dodge Grand Caravan SE
No matter what you fix, there will always be something else to fix..
"Warranty" is just another way of postponing the inevitable.