2014 ISX15 600 QuickServe question

[Flatbed]

I am in the process of swapping a 2012 ISX15 485 (2250) over to a recently overhauled 2014 ISX15 600 (2350). Rawze hooked me up with the file for the conversion. The 600 came out of a wrecker and the plate on the engine says ISX15 600, however QuickServe dataplate shows the model as a ISX15 550. Not that it really matters, but I am curious if there is a difference between the two? Were there certain configurations, such as wreckers, that were turned up?