Hard to see on my phone, but it looks like solid axle, passenger drop in the first picture? Do you know if the shop in Utah use an off the shelf axle in it or something custom?
I was going to get to that, It's actually very interesting what they did. This sort of modification was very common in the 70's for import pick-ups. Most of the Nissan and Toyotas got a modified Jeep front axle and some even got really old closed knuckle axles. There were a lot of companies offering kits or conversions back then but a few were super legit, like the Toyota Wolverine & Lowe 620.
This particular truck was done with a bunch of parts made specifically for the conversion by Spicer, they built a Dana 30 with application specific 3.90 ring and pinion, flat top knuckles and it uses the stock Mitsubishi brakes. For the transfer case they made a variant of the Dana 20 called the T100a, I can't find a lot of information on it but it seems aside from the cast iron "reverse Texas" divorce adapter it seems like a normal Dana 20. It's really neat that they put so much effort into these conversions, It's hard to imagine a company like Spicer tooling up to make a bunch of weird stuff for a Mitsubishi.
The suspension was done by Rancho, unfortunately all of those parts are now broken or missing and no longer available so I'm going to have to custom make some stuff there. Other than those Rancho parts everything else still seems available (service parts) it shouldn't ever need new knuckles or R&P but it's a safe bet those are no longer available. The knuckles look like little baby Chevy flat tops
Here's the crossmember they made to carry the transfer case.