Right there with you Rob. When I had cataract surgery, I had new closeup lens instead or long distance. (I wouldn't suggest that to anyone...seemed like a great idea at the time.)
But yes, I've done the same as you recommend; xacto the back side, and square-up the ends with a file...and I make custom sanding tools with small pieces of wood and cut adhesive-backed sandpaper to fit in the slits.
Bio, the old way was Playtex pantyhose, and I can't remember the color that was a match...Nude or Natural maybe? Someone here remembers, perhaps?