the oil fill location is on the other valve cover from one to the other, nothing major they say the 99-00 are a bit stronger~ but ive never seen it confirmed.
I've heard this as well. Also the 99-00 windsor motors have 13 valve cover bolts where as the 01-04 romeos have 11. The romeos have a 6 bolt crank and the windsors have a 8 bolt crank. Haven't heard anything official between one being stronger than the other.