Doing a fluid change.  Searched online and went to the local parts store.  All listed the same pan gasket for my 59 Edsel with a PRNDL 2 speed auto.  An almost square gasket. A TOS 18106.  But under the car the pan has a round bump out. TOS 18109 looks like the correct gasket.  Under FOMOCO is raised letters and numbers:
B9AP-7006B
#4
and under that stamped in is:
PBR-A-155903
292

What is this thing?  Pretty sure this thing is also aluminum if that helps.  I am going off a 59 Edsel manual so if this is something different, I need to know for the right fluid type and capacity etc.   Thanks for your help.

1959 Edsel Ranger, 1916 Ford "speedster"
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