New to the forum, Stepside bed questions

[Sweden64]

I am working on a -64 Stepside in Sweden and i dont have a assembly manual for my truck and I bought it in pieces so I have no idea how stuff where fitted togheter

But maybe someone can help me???

Does any one know the dimensions of the cross sills??
What i have understod the 60-66 are diffrent from earlier years?
http://www.mar-k.com/bed_side_interchange_gm.aspx

Do i put the bedsides directly on the cross sills or should it be wood between the cross sill and bedside?

Would be wonderful if someone has a reassembly picture/describition of that

/C