Yes, they will fit just fine. '87 is the cutoff for fitment, although the Blazer and Suburban stayed with the same body to '91, so wheels from one of this up to '91 will also work. You may have to do some ligth grinding in the center hole, late Ralleys have 6 "tabs" in the center bore for aligning them on the later axle pilots. These will interfere with fitment on earlier trucks. Nothing to that, really. Just grind them down until they match the larger part of the center bore. If you have the rivets that hold the front drums to the hubs, those will need to be taken out as well, as they will interfere with the wheel bolting down solidly.