Gary,
Your water leak is not caused by the awning not closing evenly. The leak is most probably caused by the "box" that Beaver cut into the wall to mount the awning into not being sealed properly. Even if you remove the awning, you will still have the "box" that is cut into the wall, and therefore the same leak. You just need to repair the leak, and that will sometimes but not always require removing the awning to reseal the mounting box.
Getting the awning to close evenly after you have inadvertently stretched out the fabric is a very easy process. Just roll out the awning manually until you see the bare roller and install several layers of duct tape in the area where the fabric is stretched. This may take several attempts to enlarge the roller enough to make the awning close evenly, but it will happen.
As for removing the Girard and replacing it with a Carefree awning. That will be expensive, lower the value of your coach, and leave you with an awning that most owners classify as junk. My first coach had a Carefree awning, and you could not give me another one.
Gerald