[BlueJeep]

Ah, you have a long bed. I think we were all assuming it was a short bed, but as I look back through the pictures I see that now. Stick with the extended cab frame, and mount the cab first and see how the box fits on it. I'd guess at the worst, you'll have to trim a couple inches off the front of the box and out of the running boards, which should be pretty easy.

I can't really give too close of box advice, since mine was a 1-ton with a 9 foot bed. I'm making new bed sides that fit the wheelbase, and cutting everything else down to match. I'm making new ones so that I can make them taller, since I'm losing bed depth with mounting my cab low on the s10 frame.