Your best course of action is to have a read of the model history section, it'll give you a feel for what bikes came when and how the timeline ran.

Without bothering to double check, I believe the PGM 1 was on the MC16, 2 on the MC18, 3 on the MC21 and 4 on the MC28.

Why would you want to retrofit it, and to what?
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MC21SP Plaything
BMW F800GS Bumblebee
Triumph 9551 Daytona Big boys toy
FJ1100 Sporting relic
GTS1000 oddball