Hello, my friend and I will soon be handed over a Passat TDI, it is the penultimate model Bj cirka 2000. However, this one is unfortunately equipped. Now I would like to retrofit at least a radio remote control, he has central locking, there is perhaps some retrofit kit, where you just put up a box and ready?! He certainly has everything prepared for it. Besides, I would still be interested in what a retrofit ung with a preheater costs incl. installation. greetings jeto