Stepside Bed dimensions.

Length 83" (6' 11")
width 48.5" (inside of bed)
width upper rail 57.5"
inside of bed front, 14" deep
15-7/8" at height of outer rail.

These dimensions are from my '83 J10 Stepside

A '50's vintage Willys pickup was very
similiar:  81" long... everything else the same.

john-at-wagoneers.com