Putting a 310 in where a 270 was previously.
The only physical difference is the bell housings.
I will cut to the chase and just post pictures.
The first are the 270 and second set are the 310.
The 310 is much beefier in the support webbing than the 270. I have not torn into the insides of either so do not know if there are extra frictions or plates. This is only a physical difference from the exterior. All the plugs, linkages etc are identical.
The 270 was from 96 528, the 310 is from a 95 525 (they claim). Not positive on the 2nd.