I really don't want to keep beating a dead horse, but I keep hearing from folks who aren't aware of the options/consequences of the various trunks.
Trunks come in a variety of makes, sizes, prices and shapes, BUT, they all fall into only three categories when it comes to mounting them to the bike, stock rack or an after-market rack.
(1) Only Givi monoKEY trunks can be attached directly to an after-market rack using either Givi or SW-Motech mounting kits. (I'll contradict myself by saying, JC-Whitney / Sears may sometimes fit the mounting kit).
(2) All other brand trunks will REQUIRE a universal mounting plate that usually comes with the trunk. The universal mounting plate can be attached to the stock rack. This includes the Kawasaki trunk often sold with, or offered by, the dealers.
(3) The Corbin Large trunk & small smuggler are exceptions to the rule as they attach to the grab-rails or in place of the Corbin removable passenger seat.
There are advantages/disadvantages to all methods of attachment. The monoKEY fits snugly and securely with minimal "bobble" but, unless the rack is adjustable, it's in a fixed location and may not fit every size passenger.
All other brands using a universal mounting plate offer some degree of adjustability in positioning the plate/trunk on the rack, but at the price of another layer (OR two) of plastic between the rack & trunk.
I hope this information helps people before they but a trunk and are then disapointed in their mounting options.