Corvette Magazine Online has a good article for removing sunvisors on a C4. I recently went through this when I removed mine. It was with some trepidaton that I removed 'em; I couldn't find an in-depth description in the
GM service manual or the
Hayne's book, and I was worried about the tension on the spring underneath the retainer. This article explains it all - except that I don't think you
can save the clips that hold the retainer; just get new ones.

Check out the article:
http://www.corvettemagazine.com/2001...r/visorpg1.asp