Can't switch stocks, as the Model 7 is shorter. Also, the I don't think that the Model 7 has the guide rail slot in the bolt head (don't have one to look at right now), and the extractor on the Model 7 (as originally designed) is bigger for some reason. Again, I don't have one currently to see if it's still that way.
I think that the point was to have the most compact full strength action available.