I will be installing YS4Z-7048-AA in the used transmission. See pictures. Has no spring. The flat side is installed toward the inside of the iB/5 transmission and the other side faces out as installed on both the original and used transmissions.
I ordered 2 seals one for the used transmission and the other for my original transmission. The info stamped on the flat side of the seals is:
CN1Z-7048-A maid in Brazil FORD 437A 96WT-7048-A9A BRUSS 11 >FE/ACM< AS 21,5X48X8,4 RF Ford specs this one for my 2013
YS4Z-7048-AA maid in Spain FORD F437A 96WT-7048-A9A BRUSS 15 >FE/ACM< AS 21,5X48X8,4 RF Ford specs this one for the used 2011 transmission.
They both appear to be dimensionnaly the same.
I just discovered that during assembly the seal is inserted from inside the case.
The YT vid shows the ST 6 speed transmission and shows the flat side out.

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