2001 GMC Sierra Dashboard display issues on my 2001 GMC Sie

For about 2 weeks now my dashboard has been having intermittent issues, it started out when I was listening to a CD or my iPod in my truck all of my Gauges would would shut off and my dash would kind of reset itself, and my radio would switch to the radio. Last week, when I was driving everything went out, the gauges dropped to zero, the message center shut off, the odometer display shut off, as well as the radio. The next day they all came back on. Two days later, it happened again, so frustrated I took my truck to the dealer for service they told me that the problem was the ignition harness shorting out because of the autostart/alarm I had on he vehicle, so I told them to fix the problem, they removed the autostart and replaced the ignition harness and said the problem was fixed, 5 minutes after leaving the dealership, it happened again, everything shut off. What could it be? Another Dealership in town said it sounded like a body control module? But after paying a 500 bill at one dealership, I'm apprehensive about taking it back to have a part that costs 330 dollars replaced. I only make 500 a week, please help.