A904 transmission
Think of it this way, A filter extension isn't really necessary. The fill level is the same regardless of which pan you are using. A deep pan just holds more but it doesn't change where "full" is in the dipstick.
Pan Kit P4007886AC | Mopar Online Parts
Some do and some are just the pan. Mopar Performance has a "Kit" for a Jeep that also works on a 904. It comes with a deep pan with drain plug, filter and extension, and a pan gasket. Even the bolts.
Think of it this way, A filter extension isn't really necessary. The fill level is the same regardless of which pan you are using. A deep pan just holds more but it doesn't change where "full" is in the dipstick.
Pan Kit P4007886AC | Mopar Online Parts