So, I've tried a number of things and still could not reproduce the turn signal lens to any degree of satisfaction and had been chewing on this project. I recently acquired a 3D printer off the local CL. This new to me tool allows for certain possibilities. I had the lens and the frame scanned. Then, I attempted to print some samples. Mind you, I still do not know what I am doing with the 3D printer.
As scanned, the plastic lens does not fit into the frame. Once freed from the frame (I had to cut up the frame to do so), the plastic lens curled up. Also, the flanges at the edged of the plastic lens were molded around the metal frame; These flanges will have to be straightened out.
The next step is to get professional help in manipulating the scanned files...