On a 2002, which is what I know about really, I always put the head of the bolt on the guibo and the nut on the steel flange because as said above it makes it easier to tighten without putting twist on the Guibo…My understanding is another reason that it’s done like that is that when the guibo flexes It can work on the nut to loosen it if placed on guibo. Not an expert/don’t really know/not a mechanic/that’s just how I do mine.
Barney
Barney