Most of the offroading in the hills is for bikes,,,alot of black diamond stuff cause of steepness and alot of erosion.
The Pine Mtn. road isn't very hard except a couple washed out places (I was there 2 years ago, don't know what its like now) You have to turn around before the "stairs". I'd be afaid to take a SWB down them.
The thing neat on Pine Mtn. Trail is the big Rock formations called Castle Rocks. You drive around and thru that area.
From the top of the SLO grade, Santa Margarita exit off 101, thru town turn onto windy 58 ,,go about 20 miles,,turn in where USFS graphic sign is.
Couple nice free campground in this area.
I haven't done Garcia. Its not as far in as Pine Mtn. A small free campground is at the turnoff for Garcia.

dave h.
'89 Raider V6 5spd;Aisin Hubs;; Gen2 LS: frt. brakes, rear coils;U.C.arms;R.trailing arms;idler arm; rear LSD axle w.disc brakes ;2 battery system for Dog's fan; relocated ECU; custom bumpers;J.Baker receiver;Conferr roofrack; t-bar crank.