To be continued once I have it sorted and presentable...
Grime is implying you found that like that!Ok, I am cleaning up all the grime on this thing right now...
There's some sort of thinner sleeve inside you can barely see because it's quite tight but it's smooth and thinner than a fatboy knob. Whatever was done would have necessitated extending the central rod quite a bit.That adjustment knob looks press fit onto the factory piece. Considering it uses a standard production Fatboy head and not a bottom dial or red dot type blade tray my gut is saying someone worked in a machine shop, liked his Fatboy and had some fun.