Hi elephant, I've grown one of these magnificent plants too, and this year it produced a flower on the biggest of the 8 stems and it developed lots of tiny bananas but unfortunately the flower stem broke off before it had fully ripened. sorry thats enough about me.
You can remove a sucker with the aid of a sharp spade by cutting down between the main stem the sucker, being very careful not to damage the main stem, try to get plenty of root on the cutting and pot it up using some multi purpose compost and keep it inside over winter.
There is an article on this in this months bbc gardeners world, showing the various steps to take.
Good Luck Tbird+