I have no idea what you are driving/ rving in, but if you have something short, you should be able to make it to some of the spots on Shadow mountain. From Gros Ventre Campground, head towards Kelly. Take Antelope Flats Road which eventually turns into Shadow Mountain Road. We drove it two weeks ago (without the tt) and found a couple of small trailers and a class C back there. Don't go too far though, especially if you are towing. There are some sites with incredible views of the Tetons. A good map is your friend.I would return the way I came as further down the road it will get tight. We have a tt 32' in total length and could have made it to the first couple of sites going slow.
There is also Atherton Campground right in that area, but we didn't check it out.
http://www.fs.usda.gov/recarea/btnf/recreation/camping-cabins/recarea/?recid=71623&actid=29
And the site on top of Shadow Mountain makes an excellent panorama shot location.