quickest way to see if you have a 420 or a 560 is by:

a) check to see what kind of wood you have. If you have burlwood(dark color wood with "birdseye" appearance) then its a 560. If you have zebrano(wood with parallel stripes) then you have a 420.

b) Open the hood and see how many "snorkels" you have going to the airfilter. If you have one on each side(2 total) then its a 560. If you only have one snorkel to the airfilter.. then its a 420.

Sorry to hear you *might* have gotten duped into a 420 when you thought you're gettting a 560.