273 engine swap into a Jeep CJ5

obviously the factory didn't do it.. it also had a amc 360 in it.. freaking thing was fast.
Somebody must have pulled the drivetrain out of an old wagoneer or pickup.
Yes a factory 360 makes a CJ jump.
I have one crazy buddy that has a 74? CJ-5 he bought new, he put a built 401 in it.
That 401 opens up like a dirt track stock car, it revs fast and has tremendous torque.
When we go wheeling for a weekend, he brings a spare 3-speed and trans with him, he says they are easy to change, and every chain has a weak link.