Aside from the stuff mentioned above, going from a 60 year old transmission, drive shaft and differential to a much lower mileage correctly geared combination, you're going to save a sizeable chunk of change and eliminate a bunch of headaches.
However, if you're experienced and equipped to rebuild and set up a new R&P and want to keep your truck "stock", then maybe the various "kits" and their expense might be just the ticket.
Personally, I looked at the cost and what I'd have in the end and chose to go open. With the modern T5 transmission available for $150.-$200. and diffs, with good road gearing for $100. it just didn't make much sense to buy a bunch of high priced parts and go through all the hassle. My hats off to those that do and who can depend on their vehicle getting to and from the barn reliably.
Dave
