I've seen it done. Tammac did it to his F450. He got some 9" C channel for where the frame levels out.
He added 2 feet and therefore had a 10' bed. He had to get a longer rear shaft and then you have the lengthen your fuel system lines.
He added 2 feet and therefore had a 10' bed. He had to get a longer rear shaft and then you have the lengthen your fuel system lines.
