That's a pretty tough drivetrain. As far as the axles are concerned it should be pretty reliable at the 35"-36" tire range. The crawl ratio is plenty low enough. The engine should have plenty of power, but carbuerated would certainly not be my 1st choice.
Im sure you are chomping at the bit, thinking about behind the wheel of that bad boy,....but there really will be some issues. The 1st thing I would be concerned with is the cooling system of that SBC in a CJ5. The SBC will fit pretty tight in a 5, so stuffing a 4 core radiator with a large diameter fan is usually out of the question. The solution is usually to keep a stock sized radiator as far forward as possible and run an electric fan either pushing or pulling. That set up is not an addequate cooling system, for an SBC in many conditions. If he says he has no overheat problems at all, when asked, I would seriously question his intgrity. Not being summer time it will be hard to really test drive it, but i wopuld be very surprised to see that set up not start to run 240 and up, in 90 degree stop and go traffic(about the equivelant of rock crawling), probably border line hot pulling a grade on the highway also, in any kind of summertime heat. Also check and see how they addressed the tight placement of the distributer cap, it will be tight against the firewall or in the passenger compartment depending on the engine location, but you can get a good look into the thought process and application of problem solving by the way this particular issue is handled. Look to see if the firewall has been hacked away, or if components that were moved are duct taped and/or held in place by bailing wire. Its just a good place to look at the quality of the swap.
Steering can be a problem also, has the steering been modified to a power steering set up, these ps swaps are very often hack jobs, done without strengthening the frame or even hacking the frame up and not propperly reinforcing. Again it may be fine but its a good place to look. Check the frame at the spring hangers, and cross members for cracks, or shoddy repairs. Check if it has an anti wrap bar, it will need one. Look at the general condition of the charging system. Dip the corner of a dark rag into the D44 filler plugs and see if the gear oil is old, sparkly, stinky, milkish white, if it is, it probably isnt the end of the world, but it is a sign of poor maintenance, and a good negotiating tool.
The suspension doesnt look too tall, but its also not, as tall as you he says. I would say its sitting at about 6 inches judging by the relationship of the fenders to the 35" mt tires.
For comparison, mine is setting at about 9", above 38.50 tires.
(sensibly altered for occasional off road use)
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