There was a fairly local guy at Moparfest
about 3-4 yrs ago with a PERFECT body transfer of a 68 Charger onto a new hemi Charger underbody. The guy wasn't a pro and if memory serves, he was actually a farmer. I talked to him about it and he said that basically, they lowered the 68 body onto the cut down new one and cut/fabbed whatever they needed to, to do it! The car was black and perfect and it was exactly what the dummies running Mother Mopar SHOULD have built as the new Charger. It's do-able and you don't need to be Chip Foose, either.