Do you have detailed instructions for gasket replacement?

Good call, it does look like you will need to disconnect the engine wiring harness down at the front of the engine sensors. I would disconnect the negative side of the battery as well to avoid electrical problems. Here are the instructions which show what to do to change the valve cover gasket with torque specs as well. Check out the images (below). Let us know if you need anything else.

Thank you very much! I will review the diagrams and see if I can do it. My concern (as always) is reaching those electrical connectors way down in back of engine.

Yep, they can be tough but take your time and just remove anything that gets in your way and you should be fine, upload images if you have a problem so I can help walk you through the repair.