Track road but don't need 4WD, just very bumpy. (My Yaris made it.)
Just past the Thurra River Camping spot (MUST do the Thurra River Dunes Walk) you'll come to the lighthouse. You can go up to the lighthouse and even stay at the cabins! (Look at Parks Vic site for time and days to go up the lighthouse.) There's 2 trails around here one - West Beach Walking Trail and one just off the lighthouse. You can see an old shipwreck!