HH56 wrote:
I think your car might have had green turn signal filters so at least you would not need to find a color to make the yellowish or amber shade used before 53. Haven't looked but something that could work for red and green plus some kind of diffuser is probably sold on Amazon.

As I said, my .012 PVC was not great for the diffuser as it was too opaque and needs to be much thinner. A decent diffuser material may be what is harder to find because a fair amount of light does need to get thru. Thin white plexiglass may work better but cannot be very thick. Not much space behind it so if it gets positioned close to the bulb it will get hot and scorch or deform in the middle.