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Looks like a "bank error in the original owner's favor" because A/C was not included in the Sports Sprint package in any model year.
See this March-April 2010 CMF thread, Replies #4 and #5: https://www.concoursmustang.com/forum/index.php?topic=843.0
I clicked on that thread and the folks there do not claim the A/C was part of the Sports Sprint package. Perhaps you need to re - read it?
I have a Marti report that is only 4 years old. The car was ordered with the sports sprint option and it also has the a/c option which is also listed on the Marti report. Not sure that the Marti report would omit a/c as part of the sports sprint option if it was available for a limited time as the Marti report I have lists rocker panel moldings and wheel covers as an option even though it was part of the sports sprint package.