From the same source you reference approvingly:
John Paul II preached Antichrist: that every man is God 1of9
http://www.youtube.com/watch?v=Ls-X5BEKTSw&feature=related
This video starts with images of inverted crucifices in context of the Pope, suggesting that the Pope is the anti-Christ. Of course, I presume you know that inverted cross is a symbol of St. Peter.
You will just have to work that out with your Catholic brothers.