[rynr]

My opinion - i might be wrong:

Those two bracket kits for gz are different because one version is for GZ 1998-2002 and second one is for GZ 2003-now.

GZ 2003 and newer have deeper turn signal lights, so hardbags are 1 or 2 centimetres to the front side of bike - that's beacause they have cut away to avoid contact with rear springs.