No. The suspension on the '88-'98 GMT 400 trucks is a very different design, nothing interchanges. What you need to look for is the '73-'86 C-30/'87-'91 R30/3500 trucks. Those will have the spindles that can be swapped. You would use the original control arms, but the balljoints and at least the outer tie rod ends will have to changed to the later style.
