Not going to get into any whizzing contest here, but what Bob has described is the best way. I do, mainly, resto-mods (on non-numbers cars) and have done race cars. We usually do the entire underside in either gloss or satin black. We use stainless brake and fuel lines and braided steel brake hoses. Using a cart makes it so the painted, or more often powder coated, suspension parts are not victims of any over spray. The entire assembly process goes much smoother. And, you can pay much more attention to detail. A cart, as Bob described, would be a good investment as well as a time-saver.