I always had a lot of trouble seeing the high beam indicator, so much so I was sure the bulb was actually burned out.
I decided to clean things up and install LED bulbs and found the lens was almost totally opaque.
Click to view attachmentLooking around at the local craft store I found these for $2.99:
Click to view attachmentThe backs are silvered but a few wipes on 1000 grit wet or dry removes it. Check the blue jewel, second from the right to see the result. Lots of color choices too.
A bit of JB Weld on the back of the instrument face:
Click to view attachmentAnd inside the rubber light shroud:
Click to view attachmentAnd try it out with a blue LED:
Click to view attachmentI thought the single jewel on the instrument face might make the light too bright so I added the second into the light shroud, YMMV...
Harvey