Don't take your caravan over there at this moment is my recommendation. The 100 + Km gravel road is not too bad at all. The problem is one very short (and deep) causeway, which sometimes is difficult to pass by conventional vehicles/Caravans. The best advice is to talk with the people from Adels Grove to survey how the condition of the road is for the size of your Caravan.

Ps.: We left our Caravan in town and went with the 4 x 4 only. Also watch out for the road trains serving the nearby mine. They ride that road at 120 Km/h and after they cross with you it takes about 5 minutes for you to be able to see the road again. Too much dust.