body drop

let me get this right. all you have to do in a stock floor body drop is take the cab off, cut and re weld the front two mounts 2.5 inches lower, tne where the actual cab (firewall to back wall) goes on the frame just section a 2.5 inch piece out and weld in a filler, and relocate you body mounts that same distance down? and rebuild your hump for the tranny and shit that much higher?, and what about the old school way to do the bed?