Union Pacific needs a large area to display their sheild. So they replace two of the small panels (A&B)
with one larger one (always in section 2). Another road that uses this configuration is TFM. At first glance it appears BNSF
is using this configuration also (in section 8). But from what we have seen, there is just a large panel applied over
the corrigated panels (there will surely be someone clarifing this).
Here are a couple images of this U.P. configuration applied to one of the Walthers
Tri-level Autorack Panel set - Double small solid panels - UP configuration
Go to "Autoracks" page