D0AZ-11572-A Is the Ford part number, SW-882 is the Ford service switch number part (later Motorcraft) number. (I guess that's the right term for the SW-882 number.)
John,
The number you reference, D0AZ-11572-A, is by definition, the Ford service stock number, the number marked on the shelf and the box. It is not the Ford "part number" wich is the item in the box. If you follow the ordering chain back to actually making a replacement (or more than one in most cases) item, the number that is required to make the part is the actual Ford part number. It is sometimes called the "engineering part number" which in truth, it is. The document for the "engineering part number" says how to build the item, the materials required, other items required, testing, etc, and it also says how to mark the part - paper tag, ink stamp, etc, which you may find on many Ford replacement (NOS) parts. When the new build (aka NOS) is done, its order sheet says to further identify the item with what we see as the Ford Service Part Number. That is done in a number of ways, another paper tag, a bag, a box. The format of the number is also identified by requiring the letter "Z" in the fourth position (Lincoln and Mercury used a different letter) to signify who has the current design and procurement responsibility. This identification system applies to items of the generation of Ford vehicles we are familiar with. The new system is similar, but expanded.
The other number you referenced, SW-882, is a shorter version for convenience of the service departments. You may call it a service number, Ford calls it a "Locator Code", as in a
spot on the shelf. It uses the same approach as "service numbers", the order sheet. The intent was to keep it simple for the Ford employees in the service departments.
I base this on many years in Military Logistics while working at Ford Aerospace, and having to explain the Federal Stock Number System to Ford management.
Jim
