My 1957 original AIM differs from the reproduction AIMs currently being sold. I compared by original AIM to the copy offered by NCRS. My AIM has two sheets not found in the NCRS copy. The NCRS copy has several sheets not found in my AIM, however. The two versions also have different efffective dates on a number of sheets. To see the differences - NCRS 57 AIM Copy compared to Original 57 AIM

Given the incompleteness of the two 57 AIMs, I decided to create a single MASTER AIM that reflects all known 57 AIM sheets. Given the sharpness of detail in my original AIM, I used my original AIM as the starting point for the MASTER AIM. I used an NCRS AIM sheet if my original sheet was missing. If my original AIM and the NCRS AIM had different versions of the same sheet, I included both sheets in the MASTER AIM. I labeled the early version of the sheet as "PRIOR." I labeled the later version of the sheet as "UPDATED." Labels are generally in the upper left hand corner. Thus, for example, you will find two versions of Section E, Sheet 5.00 in the MSTER AIM. The first version is labeled "UPDATED" and the second version is labeled "PRIOR."