[MARKDTN]

Is this gas or diesel? If it is a Diesel, it may have an SAE bellhousing which would mean that it will mate with later transmissions or possibly an adapter to a TH400 exists. Does it run? I would think that you would need a heavier (C20?) front end to support the weight like a late Cummins swap. Even if it is small it is probably still pretty heavy. Parts may be an issue too. Cat does a great job keeping and/or finding parts for older units, but you pay dearly for that. If I wanted a Cat diesel power truck, I would look for 80s-90s medium duty trucks. I think parts would be easier to find, but I still think you will need a heavier front end.