Here are maps showing the location of these 1970s Massey-Ferguson engineering and field test (respectively) centres, with respect to Paris itself:
Here is Le Plessis-Robinson, at about 7 o’clock with respect to the centre of Paris, not many kilometres east of Versailees, along the N12. I used to stay at the hotel “Le Petit Versailles”, and drive, in my hired Renault Cinq, along to Le Plessis, for a day’s liaison with Jean-Claude Muller, Gilbert Delfosse, and their colleagues. In the evenings, I would sometimes go to Parly-Deux, a then-new shopping centre, within fairly easy reach of Versailles, and which seemed glittering and modern to me.
And here is Viarmes, at about 12 o’clock, near the top of the map. I remember that the drive-in to Paris on the N1 took you past Charles de Gaulle airport, whereas the flights from Birmingham came in at Orly.