One more question - since I will be taking them out of the pot would it be easier to wash the soil off the plant so I can see where they should be separated? I've done this with other plants - hostas and elephant ears, so I thought it may be easier with the banana.

Bananas are relatively strong plants. The way I do the division is using a saw and saw the two plants apart, making sure that both plants get equal proportion of the root system. Sometimes, the pseudostem may bend at the base. If that happens, be sure not to severe on the pseudostem itself. If you think rinsing them with water will help you do a better job, by all means. Otherwise, if both plants have straight pseudostem, it's easy to split them apart. Most bananas will take the division very well. Hope that helps.