Tom:
The first cross sill is located at the first angle strip hole from the front bed panel and bolts to the front bed panel. The second and third cross sills bolt approx 26-7/8" and 53-7/16" respectively from the front bed panel. The rear sill is at the back under the tailgate and bolts to the bed sides.
This information is taken from our bed assembly instructions for the 47-53 GM Short Stepside.
Hope this helps.
Last edited by Mar-Ktech; 02/12/2008 7:46 PM.
