I don't think Mel Gibson is SSPX at all. In this week's "National Catholic Register" (probably not yet on-line) there is a long story about Mr. Gibson being a guest at the "Regnum Christi Youth and Family Encounter" on Chicago's Navy Pier. It was attended by 5,000 people. I belive "Regnum Christi" is one of the newest movements in the Catholic Church and it has been blessed by JPII. Looks to me, going by the story, that the "Regnum Christi Youth and Family Encounter" was sponsored by the Legionnaires.
The first thing Mr. Gibson did when he got on the podium was to pull out his rosary beads and say "Nothing is more powerful than prayer."
Ya know, if I was as wealthy as Mr. Gibson, I would build my own parish and have it staffed by Legionnaires. Too bad Hollywood never beckoned and too bad I don't get in the habit of buying lottery tickets!
Mel Gibson attends many religious conferences, sponsored by Catholic and Protestant organizations. I know for a fact he and his family attend SSPX Masses and his daughter is entering a convent--I believe it is SSPX.
By the way, he has built his own church in LA.