That particular piece is impossible to see through. I have clear acetate as well, which is crystal clear, which I am planning on tinting with window tint sheets, I am currently using the clouded sheets to figure out the sizing and how I will connect the pieces with out wasting any of my clear material.
nice idea for the visor.
btw, you should look up this thing called VHT Niteshades. Its a spray on tint you use for car headlights/ taillights. It'll work a lot better than the window sheets