Queries about model and year identification, engine and vehicle numbers, etc.
The standard air filter on your car was the basic oiled mesh filter, the oil bath was optional but since it doesn't show on your build slip your car did not have it. The gas filter was often a dealer installed accessory.
Interesting you are chasing an overdrive problem but according to the build slip information you provided overdrive (OD) was not originally on the car. Begs the question when and who installed it as it is not that simple a job and requires adding and/or changing several parts. The R9 would be correct for the early 48 production but since yours is rather late and designated as a 49 model on the build slip suspect the OD might have come from a parts car sometime later in life.