Bed Wood Problem

[Solver]

I just got done today cutting all new oak for my bed. I got it all stained and varnished and started putting it in.As you can see in the picture I'm doing something wrong. I cut the boards as listed on GMC paul's page exactly. I have 4 1/2 inches of space to spare!Is there supposed to be 1/2 or so in between each board? I have them about touching each other. If there is 1/2 of space between each board then how can the grooving diagram be right? The bed strips are about 1 1/2 wide so that when laid on groove (3/4" each side of board) there would be no space between. But if you add up the dimensions on the page for fleetside 72 you come up with about 66 1/2". Considering the inside measurement of bed is 72" I must be missing something.What a time to find out now!! Suggestions please