2000 v70 what trans will fit?

[oldtimertoo]

Hi Guys. I have a v70 with a tranny that seems to be toast, and I need some info as to interchangability. My car has a 55-50 trans and none of the nearby Pick a Parts have one but there a number of 55-50sn. Does anyone know the difference between them and are they interchangeable? Also there is a 55-51sn. Also, they are in other models (s40, s60, s80) so even if they fit what about wiring issues? I think that if the model # is the same they should fit (but not sure) but am concerned that the sn designation may be a problem. I surely do not want to go through all the labor involved twice. If anyone knows the difference or can give me a little guidence I would really appreciate it. HELP!! Thanks