my naomi cabinet has always been "too dark" and I've endured it since it was bad but "ok" ...
comes Doom 2 and it's DARK... like I can't see anything until I am on the enemies.
So fine, I will investigate closer.
oh oh.
first sign of trouble is the toasty vga board
and then I find scorpion here
Looking to replace just the connector, I actually find ... a "truely not tested" exact same spare board I had bought a while back!

The only issue with it is the control board connector is different.
Searching spare junk parts and found the proper (left) one
Plugged it all back in and AH!! the light !! everything is working great and no more darkness!!
Another thank you to DragonMinded for that kick in the butt to look and fix the issue!