Believe it or not, I have a 3M clear tank protector on my '92. Its so clear it doesn't show up in photos. Honestly. I looked and looked through photos of the bike to find a shot of it and you just can't see it:

After some review, I've purchased the same for my '97.
http://www.ebay.com/itm/3M-TRANSPARENT- ... bb&vxp=mtr
So that's what I use. What do you all do?