Removal (8.1L)
WARNING: This page is about a different car, the 2003 GMC Sierra, 2003 GMC Cab & Chassis Sierra, 2003 Chevrolet Silverado, and 2003 Chevrolet Cab & Chassis Silverado. However, it is still accessible from the selected car via links, so may be relevant.
Disconnect the spark plug wire at the spark plug. Twist the spark plug wire 1/2 turn. Pull only on the boot in order to remove the wire from the spark plug. Disconnect the spark plug wire from the ignition coil. Twist each spark plug boot 1/2 turn. Pull only on the boot in order to remove the wire from the ignition coil.