I work as a conductor at a UPRR Auto facility in Mira Loma CA. Our main spotting area consists of 8 stub tracks which are broken into B and A pads. The B pad of each track holds five regular autoracks. The A pad holds 7 autoracks. There is a one car lengh gap between B and A pads to allow the movement of ramps to unload the cars. When you have BTTX's or what is called articulated autoracks, then less cars will fit on the pads.
The cars are spotted from west to east, and several of the stub tracks have room on the east end, after a one car cap to spot cars in the dirt. This area is called the "off-spot." Some tracks, specifically tracks 7 and 8 have room for five cars in the "off-spot."
North of the spotting area are the support tracks. Here we have 9 through tracks that run east to west. The inbound trains shove the cars in from the west. We have loads on typicially 3-5 tracks. We pull the loads from the east to spot in what we call the "south yard " that I previously described.
We have two crossovers at the east end of the support tracks. Both crossovers give us access to the 'north yard," which consists of four through tracks. Track 1 is a rip track which holds 17-23 cars. Tracks 2-4 are used for support, empties, and sometimes we spot loads on these tracks. When loads are spotted the tracks are broken up into in to 3 pads. All pads into the auto facilty are in asphalt, only the "off-spots" are on the ballast. The three pads in the north yard from west to east are A(holding 6), B( holds five), and C which holds 7 cars. Each pad is separated by one car length, except between B and A which are two car lengths.
Also, at the south end of the support tracks are two more rip tracks that hold 7 cars a piece. A contrete block wall separates the support tracks from the south potting yard. A complete concrete block wall surrounds the entire facillity.
The mainline is across a major 4 lane road. The mainline is double tracked with a parallel siding on the southiside. After an inbound train enters this siding, it then shoves the cars across a bridge over the road into the west end of the autoplant. Only one way in and out of the plant.
As previously mentioned there is plenty of room to park the cars and the truck transporters. Builing wise there is on small office in the south yard. On the southwest corner of the massive facility is one concrete tilt up wall building that houses the offices for all the companies that work here.
I hope that helps. I should also add that no tracks are straight except the tracks in the south yard. Both the supports tracks and the north yard have sweeping curves to accomodate more track in less area.