HDDP I think you don't have any luck to find a vendor for a Gearbox. For Mercedes Cars and XF is one nobody build manual gearboxes expect AMG-RACING. Here in Europe nobody is interested in manuals for DC cars. DC stands for smooth cursing in luxury. We Germans build nice and quality fast cars if you want a race car and you want do much with your hands then you have to buy a BMW M or a Porsche not a DC. All other race cars like Ferrari or Lamborghini are too expansive for normal people like we all.