All of the sliding clips and lifting blocks inside of Zippy's sunroof were brittle and broken a few years back. I ordered the 4 pieces and replaced them with the guidance of the dude in these videos. It'll take you an hour or so to watch all three...but, you'll be glad you did once diving into the project.
I hope this helps someone attempting this repair on their own.
http://www.bimmerdiy.com/diy/e36sunroof/ http://www.youtube.com/watch?v=MVo1AuBdmzM http://www.youtube.com/watch?v=rk2wv0Jc8cU (There are 3 parts)