I couldn't tell you step-by-step, but I can tell you a few things. No, the engine doesn't need to come out, but you'll be taking a lot of the top half of the engine apart. You'll need a torque wrench and some sort of guide to tell you what order to tighten down the head bolts. They have to be done in a specific order, and so many foot-pounds at a time. Chilton will have it, and everything else about that car.
There'll be a lot of wires and hoses to disconnect, it's best to use bits of masking tape and a marker to mark where the wires/hoses go.
Here's the bad part. If you screw it up and still have to take it to a mechanic, they may charge you *more* for trying it yourself. If you don't think you can handle it, don't even attempt it.