Another 904 trans ID

Date code is August 21 1989.
Used in trucks and vans from 1990 until 3 - 15 - 91.
A999 transmission with low stall converter.
Is that date from the 0251 number?
Date isn't making sense because the dude said he pulled it out of a Cordoba or Magnum. Unless it was a replacement transmission.
In that case not sure about which converter is in there. What would low stall be from the factory? Any idea?
Thanks