Thanks for the information Kevin. Glass does scratch easily but I didn't think to "do it yourself".
This is what I would end up doing.
Only do one side of the glass.
"Scratched" would take just a little more to get clean.
So
Put scrathed side on the inside of house.
Experiment on some scrap pieces. An even fade, swirl of "waves", straight lines.
Orbital sander - save the arms
*safety first - eye protection, good gloves & mask.