Nova, the ring gear is the teeth around the outside of the flywheel - just jam a big screwdriver or bar in the teeth and against the ground, and like Fumblin sez smuck the ratchet sharply to break the bolts loose [if you don't have an air wrench]
can't see the pic yer linkin w/o going thru the signin stuff - use anything that fits the holes snugly!
Bill