2007-2008 Chevy SuperRail Mounting Kit #4423 Installation

Truck Preparation
1. Check part quantities using the Parts List on Page 2.
2. Block vehicle wheels. Some vehicles may require you to raise the rear of the truck in order to make it easier to drill for installing the mounting brackets on the truck frame.
3. You may wish to remove the wheels, to give yourself greater working room.
4. If you have purchased a template, proceed to “Template Method” below; otherwise, begin with the “Layout Method.”

Marking the Bed for Drilling
Layout Method
1. See “Truck Bed Dimension Table” under “Layout Method” on Page 4 for the dimensions. Measure and mark from the back of the bed forward the values for “A” and “B”. Do this at any point on both sides of the bed.
2. Draw a line across the bed from mark to mark.
3. Find the centerline of the bed.
4. Draw a line down the middle of the bed from front to rear.
5. Center the measurement of “C” across the centerline at the front-most line you made in step 2 and mark the measurement on each side (parallel to the centerline).
6. Center the measurement of “D” for the rear most line made in step 2, and again mark the measurement on each side (parallel to the centerline). This will locate the 4 drill holes.

Template Method
1. Lay the Template in the truck bed, centering it from side-to-side, and parallel to the end of the truck bed, using the dimension “X” listed in Truck bed layout dimension table on Page 4.
2. Mark the 4 holes, while making sure the template does not move.

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