Okay I got a problem driving me crazy. My speed tach are out Fuek gauge is pegged all the way to the right past full. I read a post about it being a ground wire. I have located 3 ground wires at various points but all look good at connections. I have not undone miles of wires to check them in route. Anyone got a good ideas what else to do and will the service maual be detailed enought to know what each junction box does and follow wires. Plus could it be the brain
1996 cherokee 6cyl inline automatic

It sounds most probably like a ground. But it may just be as simple as dirty contacts. Since you already have the instrument cluster out, use an eraser and clean the contacts. It just may work.