I have a 1959 36 stepside and was looking at it last night and it looks like the bed is lower in the front . I measured from the frane to the top of the bed front and it is 20.5 in both sides. It looks like it is about 1.75 in below the indent on the back of the cab. I see in the assy manual they have spacers but no dimensions. This was not the origional bed so it was trial and error getting it on. Thanks for any advise and a pict of the back of a cab with the bed would help.