Ok, my friend has an 89 RS that has the sagging door problem that everyone from 70-92 seem to suffer. I have a few extra sets of door hinges from fourth gens and I was wondering if we could use those on his car. I mean, my doors are just as heavy and long, so I don't see why these hinges wouldn't be able to support the weight. Could they bolt up? Or would we need to drill and mount them?