what year of car do you have??
I have a 28 with the oval glass lens, but one was cracked.
I was at the local retail store and found some cheap picture frames that had the right sized glass, the bonus was the glass was concaved and added a new look instead of flat glass, and fit with little to none fabrication + look great.
They also had the same frames in flat glass, so you might want to check out some store's.
This is a lot cheaper than haveing them made, I paid about $3.75 per frame in the store, and had them installed in about half an hour.
Just an idea.
Keeping vintage Chevy alive.
