The truck is 27 years old. Rubber degrades over time, especially when exposed to the elements. Do you really think combining new and degraded bushings is a good idea? If your going to replace any of the body mount bushings you should do all of them so they match. You have no way of knowing how much the bushings have sagged over the years and the new ones will lift up their respective mounts, creating uneven stress. Not to mention the differences in flexibility.Took a closer look today and it seems the only ones that are bad are the two closest to the front of the truck . The back 2 are perfect .the middle two look ok ,the front two should be replaced expecially the very one in the front .Is it possible to do this without loosening all the mounts on one side ?