Most parts will swap over, such as the windshield, hatch, hood. One thing to keep in mind as far as doors and fenders that the trim strip is a different size and shape, so swapping around will look wierd but the components will fit no problem.
I believe that the 89-91 cars have a slightly different ft bumper shell that requires the use of 89-91 front fenrders---bottom front edge of the fender has a different curve to fit thew new nose---87-fenders with 87 nose is a bolt on to the 89 chassis---a couple of the 89-91 fender mounting tabs (in Brake duct area)may need to be removed.