Ho, ho. When I was young and dumb (as opposed to being an old fool) and with a pocket full of money, I SO wanted a Jeep. I had a pocket full of money, but not the kind that would buy a new CJ. And in the Rust Belt, old Jeeps were Swiss cheese.
So I hit on an idea: I bought a Post Office Dispatcher (based literally on the M38A1, without the 4wd and with an AMC six jammed in) and elected to replace the body with a fiberglass CJ body.
Now it bolted right in, and careful measuring had all the body mounts correct. The wiring harness was as simple as a generator set on a 1960s bicycle.
BUT. One reason the Jeep was reviled, was, safety. A kid like me would slough that off...until you realize. AMC, when it absorbed the Jeep company, stretched the CJ wheelbases (CJ-5 and CJ-6) two inches. Partly to make room for the longer in-line sixes, which replaced the Willys fours. But also because CJ-5s were developing a bad reputation for doing somersaults - in traffic or on trails, it didn't care. It was like a pogo stick - the only way it couldn't fall, was up.
The CJ-7 solved that, and later, the Wrangler's belated AMC 4, put the whole engine behind the front axle. That made it far more stable, but that was in the future.
My plastic-fantastic home-brew not-a-Jeep, had that 600-pound cast-iron six WAY OVER the front axle. It used the military 81-inch frame, which they stuck with for the Postals (and military four-cylinders) long after the civilian products got a wheelbase stretch. The engineers thought the Postal body-weight would counter the additional nose-heaviness. But I cut that off and replaced it with a fiberglass tub that had one-quarter the weight.
I drove that thing about 100 miles after I completed it - in my rural Ohio town. It scared the snot out of me. It went into storage when I went into the Navv, and never came out. I sold it while it was parked, with the buyer doing the hard stuff. It wasn't my barn, I was paying for it, so I expect he just took the body off and left the frame for the owner to clean up. I was long gone by then.
But, yeah. Today, I'd think finding a car without airbags would be a plus; but driving a tippy plastic platform in traffic? Or a little go-cart? Thanks, no. Getting squashed in traffic...hurts.