[Armadaof1]

Find a factory, Yakima, or Thule cargo basket to mount to your rack. Throw the luggage in - get a cargp net to throw ove3r the top and you're good. You definitely want a bag to cover it all, though. NO matter how tight you wrap a tarp, it will leak - and if it doesn't it will flap in the wind and scratch the paint on top.

Better yet - get a box.