New cluster did not fix the dead Gauge issues HELP

No dome lamp brightness isn't adjustable. If you look really close at profile side of the headlight switch, a finger on the part that turns comes around to push down a separate little light switch to turn on dome. Almost like a light switch on a wall. Anyway...
All except the BRAKE lamp bulb are sharing the same chassis ground, yet all get positive from separate sources. That's why so many wires. Turn and high beam bulbs operating confirms the ground and those positive sources.
All modern connectors have controlling keys or pilots so they cannot be attached wrong. That's not the case with these inst' panel connectors. It's pretty easy to push one of these on wrong, upside down, stepped sideways, both. That would also cause all sorts of problems.