Here is another angle on the engine fairing. You can clearly see the cut-outs to clear the stringers. The flanged pipe at the extreme left is particular to this test stage only, not to flight hardware. There are two known versions of the small air scoop visible above the pipe; the type you see here (large scoop shape used on non flight vehicles) and a smaller scoop visible on the JSC first stage and used on the first few flights. (See the last photo in this row.) At the bottom of the picture, you can see a cut-out in the side of the thrust structure, this is the hold down post. The hold down arms gripped the stage at these four positions using a "vice-grip" like mechansim with a preloaded force of 700,000 pounds at each point. (See the LC-39 section for more information).