Hey!
When I spoke of the 1986 600EX package I may have been thinking more of the 1500 model. To create more of a price spread between the 531 bike (660) and the bonded Al bike (1500) the 660 may have used more Shimano and less Specialized stuff. I'm a little foggy on the specifics.
Bikes that show hard use and changed parts often have been raced. The missing decals may have been a security measure, particularly in Philly.
Neat score, nonetheless. My size and color, too!
Later
Mel