Note: In 2011, the access issue to Wilson Peak through the Silver Pick basin was resolved with the opening of the "Rock of Ages" trail. This new access utilizes part of the old access roads to the Silver Pick, but the TH actually begins beyond where it use to be, and is actually in the Elk Creek drainage.
From SH145, between Placerville and Telluride, turn south onto the "Silver Pick Road," aka: CR60M, which is a graded dirt road. This turnoff is about 6.5 miles south of the intersection at Placerville with SH62. From the turnoff it will be just under 7 miles to the trailhead (6.8 appx.) In about 3.1 miles you'll come to an intersection. Do not turn - stay on the main road and in another .7 mile, you'll come to the critical intersection. At this turn, go right onto FR622. Passenger cars beyond here not advised. Avoid accidentally driving up a private drive further right. Continue up FR622 for 2.2 more miles to where the Wilson Mesa trail comes in. In the past, some would park and start hiking from here for Silver Pick Basin. Just another tenth of a mile, you turn right onto FR645. Follow it to the Rock of Ages TH as it crosses Big Bear Creek (low water crossing) and swings around the ridge that divides Silver Pick Basin from the Elk Creek drainage. There is a sizable parking area.
Plenty of at-large, primitive camping opportunities on this one. Just after you turn off SH145, and before you cross the San Miguel River, a single-track road heads off east along the north bank of the river. You may be able to finds quick, overnight spots along here. Just across the river, you may be able to find another overnight spot.
When you turn onto FR622, watch for wider spots in the road and primitive sites just off the road. This goes for FR645 as well. You can car-camp at the trailhead and approaching the TH, there are several "wider spots in the road" and a couple of pullouts.