Can "Pro Gear Shift Assistant" be added after the fact, or does it have to come from the factory? If it can be added, is it worth it?

As some of you know, I recently acquired a 2015 GS on fairly short notice. I thought the 2015 GS used the new, simplified option packages (just Std or Premium) and since "Premium" was in the description, thought my new bike had Shift Assist. Since the listing is no longer online I asked the dealer for clarification. My bike has both the Technology Package and the Touring Package and several other individual add-ons, just about every bell and whistle but no PGSA. dopeslap

Birmingham, AL
'16 R1200GS
'07 F650GS Dakar