Everyone meets at the lower lot. Take the 74 (Ortega hwy) to Hot Springs Canyon Road (Look for signs for the Lazy W Ranch). You'll see a fire station at the start of the road.
It's maybe 1/2 to 3/4 a mile down the road - you'll see a parking area and probably plenty of bikers getting ready.
The climbers take off from there, the shuttlers get a ride to the top, but will end up there.