You've seen someone take a '56 Ford Truck body and mate it to a 120 Platform frame? I don't have the measurements or the body mount locations in front of me so I can't say whether or not they line up well, nor do I know if the wheel wells and openings are proper to prevent rubbing and restriction.
Anyone can throw a body on a frame, that doesn't mean its done right. Not saying you or anyone can't do it right, just that it takes a bit more foresight than "slap some bigger bolts and some hockey pucks on it and you're good to go."
I'm thinking of how I myself would do it, meaning the body will be tucked as close to the frame as possible for balance and handling (not on a 6" body lift because I am too lazy to tuck and fit the body to the frame properly." The '56 body needs to be inspected and reinforced where it needs to be for various reason ranging from crash safety & repairing corrosion damage to flexing & rigidity on mounting points. The body needs to be trimmed, adjusted, and tweaked where the suspension, drivetrain, and other components don't meet properly and/or restrict proper function. The firewall and engine bay need to be adjusted to mate the vehicle's engine and such properly (in my case I am thinking how to fit a 2UZ-FE in the engine bay.)
When I say "extensive fabrication, wiring, and engineering" it doesn't mean you have to have a PHD from Harvard in mechanical engineering. I am saying it requires research, measurements, trial and error, fabrication, money, and lots and lots of time to do properly. Many famous fabricators aren't rocket scientists; they just know good work takes a lot more time thinking than it does wrenching. Even the guys who can slap stuff together are doing a ton of thinking before they make a cut, they just have a lot more experience and stored data in their head so they are confident enough to make a cut within a few thousandsth without laying it out before hand.
but in my mind I'm thinking like it was in my stall at work.
