Gearbox info - help needed

[Major_Sarcasm]

Hi All

Can anyone tell me, definitively, if a manual box from an F series M135i will fit an E series 135i (both being N55 powered)?

The N55 manual box in the E-series 135i/335i has the code: GS6-45BZ-THD4 (part number 23007599342)

The manual box in the M135i is: GS6-45BZ-THY8 (part number 23007617492). Are they compatible, i.e. direct fit, plug and play?

Realoem lists the THY8 as superseding the THD4. However, when looking at the THD4 page, the "superseded by THY8" has "nonexchangeable retrospectively" written next to it. Is this due to physical differences?

Does anyone know what these 4-digit suffix codes translate to? They're both "TH" but curious as to what the rest of the code is.

Thanks for any help.