How did you come up with the head of the Catholic church as a possible candidate?
VI. There is no other head of the Church but the Lord Jesus Christ: nor can the Pope of Rome, in any sense be head thereof; but is that Antichrist, that man of sin and son of perdition, that exalteth himself in the Church against Christ, and all that is called God.-- Westminster Confession of Faith, chapter 25, paragraph 6
I didn't say that the Pope would become the Antichrist, I said Anticrist would become the Pope. I think in prophecy it is clear that after the Antichrist manifests, he/it will be made the leader of all the worlds religious organizations. Believers will reject him, and be persecuted.