I'm not sure of the Sheraton's loction (although i've heard it's a nice hotel).
This map of the MetroMover is pretty good and i'm sure you can figure it out based upon the address of the Sheraton. You could also just call the Sheraton and ask them how close they are to the MetroMover.
Here's the map: http://www.co.miami-dade.fl.us/trans...omover/map.htm
Sorry i can't be of more help on this one