I’ve fixed a few glasses on machines I got cheap. There’s no silver bullet that I know of. It’s painful trial and error until you find something you’re happy with.

The enemy of good is better here. I remember wiping off attempts that looked pretty good, then proceeded to make it look worse and never could duplicate the pretty good attempt.

I just fix the opaque parts and bandaid the translucent parts as well as I can... and then start hunting for a replacement glass.

You'd have to scrape off all of the translucent area and repaint it with transparent paint, then cover it with the thin white masking.

Every backglasss I've ever tried to do anything with ends up looking worse. Some people will touch it up and then make it opaque, it's a compromise, or put a stained gel dipped lamp behind it that's a close color. Some people just take the bulb out from the back entirely.

BG are definitely the hardest item to touchup since you have to worry about matching the translucency as well as the color and thickness.

Hi,

There is an alternative accessible by everybody... But don't hope any miracle.
Print water decal of the touched up picture of the area. Clear coat the printed side.
Attach the water decal on the back of the backglass... Make it correspond with the art on the front side. Let it dry.
Paint over the back in white. Place some final clearcoat on it.
Place it over some light... Should be fine for small touch up.

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