Friends of mine when I was a teenager had a home made similar type of vehicle.
It was made from 2 1960s Holden car bodies and 4 lengths of 3" diameter steel pipe, plus a few lengths of smaller pipe for cross bracing. Car bodies had a full chasis back then. Both bodies were completely stripped of body work.
The lower chasis had only wheels, suspension and running gear. 6' above the second chasis had engine, gear box, seats, steering wheel and controls etc. Hand made linkages for the steering and brakes but the drive chain was just the original differentials and their prop shafts.
The upper differential had been swiveled sideways so that one axle spline was facing downwards, it's opposing axle spline was welded immobile. Then another prop shaft to the lower diff which had simply been swiveled upwards.
Because it was running through two diffs the gearing was incredibly low. In third gear with the engine at high revs it did about 15 mph. We used it for fishing, they had a holiday shack at one of those really shallow beaches where when the tide goes out it goes out for miles.
4 or 6 of us at a time would go out with rakes and hand spears collecting crabs and flounder. We had buckets hanging all round the side of The Jinker, as they called it. We just used to leave it running in first gear with the choke out a little bit and walk along side it so that we could drop our catches in a bucket and keep fishing. When we got too close to one end of the beach someone would climb up and turn it around to head in the opposite direction, then jump back in the water to continue fishing.
And we were teenagers, of course there was an esky full of beers too.