My dealer provided further information on this yesterday. Following is what he sent me by e-mail:
"With regard to the 3rd SCV, I ordered your tractor with a factory installed lever control. This is how this works. When you order a tractor with the dual SCV and joystick control, there is a 3rd valve already on that selective control valve. If you order the lever control and remotes to access that valve, it comes through factory installed. It can be field installed. All of the moldings come through exactly the same, there is a cut out where the lever control is supposed to go. The only difference is whether it's cut at the factory or at the dealer. If the technician takes his time and is precise in what he is doing, you shouldn't be able to discern whether it's factory or field installed. I think sometimes technicians only think of the operational aspect of things with too little attention paid to cosmetics....As far as the molding you spoke of, I think the only places you'll see that are on the slots that are always used (gear shift or range for instance) because it can be molded that way in manufacturing....The only other difference between factory and field installed is dealer cost. The net difference is in favor of the dealer for the kit to be ordered separately by about $40. But, it takes 3 hours to install one at an internal shop rate of about $50/hour. Factory installed saves the customer between $100 and $150."