what piston is number one
Generally on Chevy trucks TROY the left (drivers) front cylinder is #1 but you should probably verify with a trip to the library to check your particular model's Chilton's, or drop a dime to your local Chevy service manager.
If your standing in front of the truck facing it, it is the cylinder to the right closest to you is number one.
Front left (as viewed from the drivers seat) for a V6 motor.
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