Forget the angle iron across the frame. You want either Happijac or Torklift tie downs.
Chevy's do not have isolators but many campers do have them. I'd wait on that until you see what camper you get. If it has an isolator then no need for one in the truck. You can always just unplug the cord when you stop for the night.
You will need a 7 pin connector for the camper unless you get a Lance which uses their own 6 pin.
Be sure you leave your tailgate at home. If you bring it with you you'll have no where to put it for the trip home except inside the camper.
