Overall view of the three aft skirts.
As can be seen, all three aft skirts are missing panels, and based on the Google Maps coverage, it
appears that none of the three aft skirts were particularly complete. My
initial though was that they scavenged parts from all three to make a single
aft skirt for display on
their SRB, but a bit of research upon returning home showed that they
shipped in a complete aft skirt for the SRB display.
For additional information on the Shuttle SRBs, including an SRB exploded view
diagram, see the Kennedy Space Center's Solid
Rocket Boosters page in their NSTS
News Reference or this SRB exploded view