I have a September 1994 Volvo 850 T5. It so happened that I replaced the automatic transmission with a manual one. Now, in order to register the car as a historic vehicle in Spain, I need to restore it to its original stock condition. The problem is that there are no pre-facelift automatic transmissions (manufactured before August 1995) available for sale.

I'm wondering what would happen if I were to install a post-facelift transmission without the sensor on the gearbox. Currently, I have a manual transmission installed that also lacks the sensor, and I obtain the speed readings from the ABS sensor on the left wheel. Would it be necessary to install a control module from a post-facelift automatic transmission? If so, how can I determine the specific post-facelift control module based on its number, in order to purchase the correct one?