Has ayone installed a Yakima SkyBox 12 on thier 4R? I'd like to get this box, but want to be sure the lift gate will open all the way (the tail end seems like a good shape to allow the spoiler to pass by). Seems I'll have to go with Thule or Yakima bars so it won't scratch the roof (per other posts). I have a Yakima RocketBox, but it's old and cracked and someone had to modify the attachment system to get it to work with the lift gate - I'd like to avoid that. Thanks.