And now for the exciting conclusion to my sunglasses video.
I considered many different sources for something I could use to block light and UV for my sunglasses. I explored tinted lighting gels like they use on stage, but most of those are either tinted or UV blocking, not both. Fortunately my plan B worked well. I decided to find a local auto window tinting company and see if they had any scrap that they could let me have. The people at Pro Tint in Sandy, Utah provided me with a very generous sheet of 60% light blocking and UV screen. Thanks guys!
Now to get the film on to the sunglasses. Let me tell you what doesn't work. Heat. An instructable I saw seemed to indicate this would be a good idea, but with window tint it doesn't work. I tried an iron, I tried a heat gun. The problem is if you get it hot enough to melt the window tint the plastic of the sunglasses frame will start to deform.