Not sure even where the start is, or how much room there is. I would not camp at the start anyway. The first year we raced Vegas to Reno (2006), we camped at the start. When we got out there the night before, nobody was really there, woke up in the morning and we were blocked in. Had to wait a while before we could get the toy hauler out. Every year since then we usually go past the start, find a turnout along the highway (There are a bunch along 95), and just stay there. Then in the morning we just head back to the start, going the opposite dircetion of all the traffic.
Doug