I just did this on my own AS.
Very easy procedure.....
Get yourself safely up to the dome, remove the 3-4 screws on the hinge side of the dome, and remove the old dome.
Clean whatever you can while the dome is off, and you are already there.
Use silicone spray on a clean rag to clean and moisturize the gasket between the dome and the assemply. This will ensure the dome won't stick to the rubber gasket.
Place the new dome on the assy,Line up the lift arm with the channel in the dome, then replace the screws, being careful not to over tighten them.
Easy as pie, like 10 minutes start to finish!