Tips on returning rental car at Bordeaux St. Jean train station

It appears that I might be the first to do this and live to write about it, so here goes. All of the major rental car firms now have their return lots in a NEW, multi-story "car-park" adjacent to, but on the other side of the tracks from the main train terminal. So if you navigate to the station on GPS, you'll be on the wrong side of the tracks! Entrance to the car park is from street called Terres Bordes, BUT THERE IS ABSOLUTELY NO SIGNAGE TO INDICATE RENTAL CAR RETURN. We navigated to the car return address for Europcar: 137 R TERRES BORDES, HALL 3, N -1, CARPARK P3 INDIGO-BELCIER 6E ETAGE (137 was too new for the GPS to recognize the address number), but it got us close enough to guess that we were at the right place. Then, once you are inside the parking deck, there are small paper signs taped to support columns near the circular UP ramps that indicate CAR RETURN. Hallelujah! From there, I think it's on level 5 or 6 to the return areas. From there, it's easy as long as your luggage has wheels....no luggage trolleys or porters available. Take the parking deck elevator down to street level (0 as I recall), then down a long ramp toward the platforms, and you can walk to the platforms easily from there. With large, heavy bags, I was concerned about stairs, lifts, etc., but there are easy ramps up to the platforms from a corridor beneath the tracks with great signage showing which train to which destination, etc. Just before you enter this corridor, there's a nice new little coffee/pastry shop on the corner with a seating area where you can check your platform assignment on a nearby screen.