The coil packs live on top of the driver's side spark plugs - they have to come off to replace the plugs. IIRC there are two small bolts attaching each coil pack to the valve cover. If I were you, with the misfire you're experiencing, I'd plan to pull the plenum and replace the gasket on the chance that it's a vacuum leak that's contributing to your issue. Removing the plenum isn't all that difficult, the hardest part is getting to the bolt on the rear driver's side of the plenum. Once you have it off, replacing your plugs and wires will be much easier.