Now lets talk about cutting the 69 Mustang Mach 1 that will be used for this build. Before Allan can replace any of the Mustang body panels or rusty parts on this 69 Mustang he has to get it mounted on 89 Lincoln. If he cuts too much of it away the body will twist and become deformed.
The original plan was to weld braces inside the body but the body turned out to very strong even without the undercarriage so the braces were not used. They would only get in the way anyway.
So as you figured the complete undercarriage was cut away from the body leaving everything from the rocker panels out and up in place. Of course the doors were removed to make the body easier to work with.
With all of this work done Allan can now start fitting the 69 Mustang Mach 1 body to the 89 Lincoln Mark VII undercarriage. It's a slow tedious job having to measure multiple times to make sure than everything is straight, square, and lined up correctly. And, Allan will make sure that it is correct.