Should I look for a longhorn bed....

[hugger6933]

Or use my long 3/4 ton frame for my 71 cab chassis? I kinda got a dually bed build for my one ton, I have a higher gear rear end from a square to get rid of the 5:38's that are there now. The truck has a small block 400 and a 4 speed in it now I may go NV4500 or T400 or if I go crazy I might go 4L80E. My next problem is figuring the bed it has a flat on it but it really is from a shorter framed truck someone threw on there and is too short[ cab to bed gap is like a foot]
I have thought about using a longhorn bed but I don't have any leads on one and have not looked as yet. What would you do to build the truck besides put it on a short bed frame with 5 lug suspension[I do have the bed and the frame, suspension]