The PO Box checks out, indeed. However, if you look at the address, it is for the fighter group (147th Fighter Group) that was the "parent" of the fighter squadron to which Bush was assigned. The alleged documents' return address is for the squadron. Did the squadron have the same post-office box as the group?
In the authentic records (page 3), Bush's squadron is designated "111th Fighter Interceptor Squadron." On the correspondence among the authentic documents, however, the address is "147th Fighter Group." Interesting to note as well that the document (page 6)--official orders, in fact--are headed with "Department of the Air Force/Headquarters 147th Fighter Group (TNG)/Ellington Air Force Base, Texas 77030." Are there any other authenticated correspondence/orders that show the squadron's address as "111th Fighter Interceptor Squadron" or is headed "111th Fighter Squadron"?
Also, the home address for George Bush on the records shown on pages 7 and 11--and dated "1 Dec 69" and "9 Dec 68," respectively--is "5000 Longmont, Apt. 8/Houston, Texas 77027;" the home address shown on page 8 on a document dated 15 September 1971 is "2039 One Half South Blvd/Houston TX 77086." The alleged "memorandum" to George Bush dated 1 May 1972 lists the 1968 address as his home address. Did he move back to the Longmont address between September 1971 and May 1972?
Another good question.