Well, yeah, Its probably a shot sending unit. But, your best bet for info on a GMC product would be one of the Chevrolet-GMC truck forums. Check on yahoo. They know a heck of a lot more about GM products than most of us do.
Good Luck, and God Bless,
Dave.

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Currently Driving:
1986 Mercedes Benz 560SEL
1994 Lincoln Town Car
1994 Cadillac Deville
1985 Lincoln Town Car- Retired

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