dash cluster help

Yes disconnect the battery. Those wires going to the Ammeter have straight battery power going to them. Be careful with the speedo cable. There is a little tab you push down and then pull out with. The plastic end with the tab may be brittle and easily breaks if you're too rough with it.

412 stroker, check your light switch in the dash cluster. It's a bear but you can remove it without removing the cluster. I just replaced the one in my 67 Valiant because I couldn't get the dash to light up. I put an ohmmeter on it and there was no continuity when I pulled the switch out. Replaced it with a backup switch I had and it works great now.