I agree. And I think the same is true for any E36 repair documents.
All we can do is repair to original specs. That means we can buy brand new sheet metal, and spot weld it in the same way as the originals. The good news is that those trunk floor panels are still available ... no need for a body-in-white should it happen. It's definitely a more extensive (and expensive!) repair than a broken 944 control arm would be, but should it happen, it won't be the end of the world.
BTW, Rob, I'm sure the same is true for the E46 ... even if that bulletin didn't exist, replacement original body parts (vs. smaller reinforcements) could be purchased and welded in.