Help: 98 Dump truck battery oops

There are 2 10 gage ground wires connected to the negative battery post along with the main cable. They run together up to an isolated ground on the engine above the ecm. While changing a battery today, I connected one of these wires to the positive post for a few exciting seconds. I corrected the wiring and checked for blown fuses. Now when I turn the key to 'run' I get no panel lights nor odometer except for 'fluids' ; no gauges reset. And.......the windshield wipers run even the off position. Starter works (i bumped it) Lights work. I have not started the engine afraid of doing further damage. Can't find any fried wires. Any suggestions?