I've got a 2000 F250 diesel shortbed with a FWC camper. The camper sticks out about 12" beyond the bed of the truck, just enough that I can't use a rear motorcycle hitch carrier/mototote without some sort of extension. The extension adds wobble and reduces carrying capacity enough that it doesn't look like it's a good idea.
Put a Reese solid bar extension on the rear,there rated way heavier than your bike is..Then put a wobble stopper on it for the wobble they sometimes give..
My 18" is rated for 400# and 600# with WD if memory serves..