I would use the drive train from the bread truck as long as the front spindles and front brakes will adapt to the COEs shorter front axle as Grigg here on the Stovebolt page has been working out the bugs on.Just remember if you go the diesel route and don't use a matching drive train you will have to at least change the rear end for gears that will work with the lower rpm engine.
it would be easier just to adapt the cab to the whole chassis...IF the chassis ( track width )is narrow enough
