Two of my friends had old jeeps {a 52 pickup and a 54 panel delivery} were excellent 4x4`s, would go anywhere! Not fast mind ya, 55 mph and they sound like there going to blow up! the 52 had the O.E.M. straight six in it and 5:23 ratio in the differentials {yea real low geared} and yea horrible mileage!
The panel had a 283 conversion, with 5:38 diff ratios, plenty of power! But still Sounded like it was bieng tortured at 55 mph. Many broken axels and xfer cases later he finally sold it to a young kid.
It lasted him about a month then I saw it no more after that.
Fun 4X4`s if you are not in a hurry to get anywhere.