Jeff, Lots of options here. The sticky thread by Grigg at the top of the big bolts section would be good to read through if you haven't already. I do a fair amount of chassis swaps at my shop and although they have benefits, it can certainly be a lot of problem solving.
I too use a 46 2-ton for my business. It has the stock running gear. The only thing I did was to add the front disc brakes and dual circuit vacuum boosted master so that it would stop. My employee's drive ti probably more than I do, so it had to stop and do it well. I have had well over 10,000 pounds on the bed of my truck and it routinely gets 5-7000 pounds on it. I do run it on the interstate, but it does't do very well over 50mph.
Tell your neighbor good luck and I can say first hand that a 46 2-ton is a great marketing tool.
