Jordan - one way to know for certain, look under the 550 section of this forum and review all the Maintenance and Service Bulletins between the years. Some times, you may see a reference to Dealer installed factory upgrades under warranty or service intervals.
It's usually a good indicator of a design or part change. Not foolproof, but for fools like us, should be good enough. The absence of these types of notices is also a high likelihood of cross year compatibility (where there is no known, specific difference).
