Change/Swap Transmission Control Module (TCM)

[Romy]

I'm curious if anyone knows if it's possible to swap TCM's between years. I'd like to be able to use FreeSSM to talk to my transmission, but my 2001 apparently has the older TCM which will not communicate with FreeSSM. Supposedly they switched TCMs sometime throughout the 2001 model year and some 2001 cars work with FreeSSM, and others don't (read that on the Forester forum).

Anyhow, seeing as the 4eat is the same for 2.5L cars from mid 1999 - 2003 (or so) does anyone know if swapping to a 2002 or 2003 TCM will allow FreeSSM to read the tranny trouble codes? Is it that simple, or would more than just the TCM need to be changed?