I have a '07 620i and an opportunity to acquire a new DFK brand cab kit for it. DFK began offering these for Gators beginning in 2012,which was the last year JD offered the 620i and the first year of the 625i. Neither DFK,Koplin nor Curtis mention kits for the 620i,however, given the typical Detroit mentality of making the least cost related changes for 'a new model year' ,I'm not convinced (yet) that this cab kit won't also fit the 620i.

A friend's 2016 HPX is the very same 'platform' as my 620i with the exception of 1" smaller wheels and a carburetor versus F/I;an example of that 'Detroit mentality'.

The JD dealers that I've contacted for comparison information (i.e. comparing frame & ROPS part numbers for 620i vs. 625i) have been moderately worthless;and I understand that this isn't a typical situation.
The best person to answer these questions would of course be a JD tech. I've listened to a lot of theory;entertaining,but certainly not conclusive......

SAMinIN