I found them in 2008 by looking for weird entries in NARA's Master Location Record. Turns out they were mislabeled.
@Joshua_Pollack Things with MLR entries but no Finding Aid entries. Things marked as classified but kept in unclassified areas. Etc.
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@Joshua_Pollack Things with MLR entries but no Finding Aid entries. Things marked as classified but kept in unclassified areas. Etc.