Unfortunately, we did not get the opportunity to visit Venezuela, but we understand there are beautiful areas of the country.
There are FUSO and Isuzu NPR here but not 4X4.
4x4 is highly over-rated for what you are going to do. Basically, it's unnecessary on the camper for your mission.
Most of the archeological sites are connected by market town roads, or, at worst, chicken bus roads. Those roads may be single lane shelf roads, but they don't require 4x4. All the chicken buses are 4x2.
Once you get to the village that's closest to the site, you will need to change to a burro, or, at best, a HiLux, anyway. No medium sized truck can get down the tracks that lead to the remote non-tourist sites you'll probably be documenting.
The dirty little secret of full-time overlanding is that the interesting places in the world are connected by market town roads. Some require you to go down a chicken bus road for the last leg. All the trucks and buses on those roads are 4x2.
More than a few overlanders I interviewed circumnavigated the world and never engaged their four wheel drive for themselves (a few used it to tow others out of sand, etc.).
4x4 is useful if you seek out places that require it, but those places are often just that, a place to demonstrate the need for 4x4 rather than a place you'd go to otherwise.
The vehicles you see here on ExPo are heavily skewed to the U.S. market, in which overlanding mostly means 4x4 camping. That's a very different paradigm from the global definition of overlanding.
Of the vehicles that are actually out there overlanding around the world, the vast majority are European 4x2 vans. You don't need 4x4 to go overlanding, especially where you are headed.
For your mission, as stated, I don't think you will need 4x4. By the time you would need 4x4 you would already be on a track too small for anything but the HiLux. For the remote sites you'll need to get on burros anyway.
Considering your location, I recommend you find a used Argentinian Mercedes chassis Caravan/RV around 8 meters in overall length. It will be a very durable chassis that you can get repaired using locally available parts.
When we were there, the prices were very low and used units were relatively plentiful.
If you need to, you can reconfigure the interior to support four bunk beds, dedicated work stations, etc.
That will make a great base camp vehicle.
Pair that up with a used Toyota HiLux diesel 4x4 that you can buy locally and you will have a perfect combination for your expedition.
For recovery, you may want to put a winch on the HiLux, but on the camper all you'll need is a European truck tow bar & pinion, which the Caravan/RV will probably already have.
Find a shorter version of one of these:
For example, is it too tiring or uncomfortable to drive a cabover such as Mitsubishi FUSO for long perdios of time?
If you leave it stock, then yes, it can be punishing.
Things to do, in order of priority:
1. Air seat. If you are contemplating traveling with a spouse or significant other, don't drive a kilometer without replacing the passenger seat with an air suspension seat. You may be able to modify one from an over-the-road/18 wheel truck to fit. You can find the details of the seats we used on our build site. I don't know if those are available in your market or not.
2. Acoustic lining. This product will be available in your market. Go to a local car stereo shop and buy the adhesive acoustic mat material. Take apart the cab (remove the seats, floor liner, head liner, trim, etc.). This job will take you about an hour. It really comes apart very quickly. Apply the acoustic mat to all of the interior areas of the cab metal. You will not believe the difference. Our cab came out spooky quiet. It's much, much quieter than a U.S. market full-size van, for instance. It is a bit bizarre to be sitting on top of a diesel engine that you can barely hear run.
3. Aftermarket shocks. We used Bilsteins. If I had it to do over again, I'd modify the truck for dual shocks.
4. Custom spring packs. You can probably find this capability/product in the truck repair neighborhoods of a major market town or any medium sized city. Once the truck is built and completely loaded for travel, go to a flat truck scale and weigh each corner of the truck. Find a shop that repairs truck springs. Have them add or remove leaves in your spring packs to optimize each spring pack to each corner's weight. If you can find a shop that can make custom spring packs, have them build spring packs that consist of many thin leaves rather than a few thick leaves. That will make a dramatic difference in ride quality.
Question: Do you have a research grant or a sponsor for your expedition?
