Recently purchased a 2004 is300. Fog lights work fine, but plastic cover/lense misted and lightly scratched from small stones etc. Q. Can lense be removed for cleaning. If so, any advice how best to remove/reduce damage?

 

If all of the flaws you describe are on the outside of the lens than yes it can be fixed easily by using Meguiar's PlastX and wet sanding them. If it is on the inside than you'd have to remove the fog light and put it in the oven to loosen the sealant then pry off the lens, which is much more complicated.