Quote:

I thought the cluster ground was via the screws into the dash frame?





It is. Lots of things can happen when you loose the ground. Two main points. The printed circuit board needs to grounded to the main housing VIA the screws that hold the printed board to the cluster. Most likely only one controls the ground so make sure all are tight. Second is the screws that hold the cluster to the dash frame. It cant be loose from there. Best way is to install a ground wire from the cluster housing to a good body ground and then make sure all the screws that hold the printed circuit board in are tight,

When you hit the brights the indicator must of stole the printed circuits board ground.

Head lights are a different circuit and have zero bearing on your problem.