Where is the spark plug on a 2006 polaris sportsman 450?

Just changed a plug this AM. Remove the right side panel. On top of the cylinder (top of engine) there is an orange or red rubber plug. Spark Plug is under this waterproof plug. Need a 5/8" spark plug socket and about a 3 inch extention to remove plug. Kind of a pain to get to. Tight area to work in. Good Luck!