It would be a little easier than installing a V8, but it would then not be a restoration. The 194 is longer than the 216, so the radiator will have to be moved forward and you will need to fab up side motor mounts or install the same front cross member that would be used for a V8 transplant. You can't use the later transmission without getting rid of your torque tube rear, your original transmission won't bolt to the new bellhousing and the old bellhousing can't be bolted to the newer engine. If the engine needs rebuilding, it would not be a good swap.