lets get to the .79 solution. I discovered this by accident after reading about lens caps (hideous expensive!) and vellum. I would not know what vellum was if you fed it to me with cabbage so I asked the wife, and then, tried something. I am remodeling the house so I have some armstrong self stick tiles around for like closet floors and stuff. the backing paper is a weird semi organic, semi plastic paper to stick to the tile, but not let it dry out, but not stick real hard. It has a neato translucent property.
So....
I cut it into small rectangles and made is as long as the light housing is wide (no pictures, all my victims are together in the store...)
then I folded the edges back to give a glueing surface, and used midwest/simply speaker glue to fasten it in side the housing.
considering the viewing angle is from 25* to maybe 140* this sets up the focul length...25* - farther out, 140 - closer to the lights
it then acts as a glowing screen in the target color, softening greatly the LED spotlight effect. the picture I gave is a fairly recent restore of a fisher MC-3010. If had 3 sickly glowing incandescants that were power hungry, now it has 6 3mm 5000K leds held to around 11-13ma and the meters have 2 and all the 8 track track lights, stereo etc, are leds in the correct color.
so the .79 part? goto lowes or home depot and buy one tile for .79 so ugly, your wife wont want it, then just peel off the backing as you need it