Yep, I agree with the last post. The only thing to worry about are the capacitors. Some setups will combine the capacitors with a resistive circuit so they will discharge quickly after you power down, but you can't rely on that.
Like the last post said, you can discharge a capacitor by shorting out the leads with an insulated screwdriver or pliers. You can check if they are charged by using a multimeter across the leads.
If you don't want to discharge them yourself, then wait an hour

. I noticed this to be long enough to discharge capacitors in TVs I've worked on.
Just don;t touvh anything you don't have to
