bed side to top dimentions

[DemkoG]

I am restoring a 1970 blazer and it is not in the best shape and I am not confident that the sides are square any more. I am going to be doing some bed side repairs and will eventually be cleaning up the top. I was looking around the site and could not find the factory dimension for the width of the bed and the length between top mounting bolts, that way I can make a jig and get everything back to square while I cut up the floor and structural parts. Then later bolt the hard top to it when I go to fix it and hopefully bolt the two back together with no problems.
Thank you guys in advanced.