[sandcruiser]

when I first got into driving offroad, a buddy gave me some excellent advice:

go drive. when you get stuck or break something, ask yourself "why". Then fix the problem.

you would probably be surprised at just how much you can do with a totally stock rig on street tires. Sure, you'll get stuck. Travel with a friend or two and they can pull you out.

Of course, before any of that..... fix any/all leaks, make sure your brakes and steering are in excellent shape.

finally: x2 on street tires for Pismo.... they'll work just fine. That event will be a good opportunity to see what other people are doing, and learn from their success