And here is one of the sections (1st pic) that had cracking in the paint that couldn’t be seen until backlit. And the next few pics are how I chose to correct the problem, I used this small area as a test section. Because this cracking couldn’t be seen from the front til backlit, and that id previously sealed the glass with triple thick, I just sprayed some dark blue on to hide the cracks, and later after this blue had dried I sprayed on some silver to completely block out the light. Because the glass was sealed with triple thick, there was no danger of the different coloured blue I used leeching through to the front of the glass. These pics are before the silver went on. Even without the silver it all but blocks out the light I had shining behind it. Simple but effective fix me thinks!!

Notice I have a few small areas of missing paint to touch up.. I’ll probably just do these with waterbased artists acrylics.