GMC 2003 C4C042 Owner's Manual page 237

A. Shackle Bracket
B. Tow Bar
C. Lift Chain
D. Hardwood Beam
5. Raise the vehicle to the required height.
5-12
Towing the Vehicle with the Front Bumper Installed
1. Connect and lock the lift chains to the front axle,
outside of the spring anchor plates as previously
shown.
2. Place a 6" x 6" x 5' hardwood beam underneath and
slightly behind the front spring shackle brackets as
previously shown.
3. Connect the lift chains to the tow bar and take up the
slack in the chains until the tow bar is within 4" of
the front bumper facing. Place a 2" x 12" x 40"
hardwood board with rubber pads against the front
bumper and secure as shown.