2000 Mazda Miata No gauge cluster illumination

Hello, I'm in need of some ideas cause i'm all out. I recently took my interior apart (took dash out to), and wired in a new radio. Upon hooking everything up (checked everything many times nothing is unplugged except both airbags) my gauge cluster illumination does not work when turning the headlights on. I checked the taillights, turn signals, and every other light (they work) i changed the dimmer switch thinking it was blown, all wires checked and getting power. I did take the gauge cluster out when i took the dash out too, so I'm sorts worried the cluster might have been damaged (it worked before so obviously something I did). I have looked around but haven't seen anything like my issue or a definite solution. Any ideas or suggestions are welcome (its been weeks without cluster lights and scurry at night).

I've checked fuses but all were fine. I did find that the middle connector of the three is the one responsible for illumination and that it was not getting a ground. Does anyone know where it goes back to ground to? i tried to trace it back but it seems as if it goes back to the fuse block.