Home made roof rack?

Has anyone attempted this? I have a '01 Reg Cab PreRunner with a shell. I'm gunna use plumbing pipe and paint it. I've got the pattern over the shell figured out, but I would like it to extend over the cab as much as possible. I want it heavy duty, plan on running 4 vertical post, anchored to the bed, up thru the shell, all holes properly sealed of course. Really just looking for pics and thoughts as I continue to brain storm. If you're wondering what I would be hauling....the heaviest object(s) would be lumber that doesn't fit in the bed, but also kayaks, mtn bikes, etc.

 

yeah a rack similar to the 4runner