You want evidence of the errors espoused by Fr. Edward Schillebeeckx before he became a peritus at Vatican II?
Am I wrong to presume that therefore you are opposed to the Pope? Do you reject the papacy of Pope Pius XII?
There are slime balls and then there are Modernists. The club of "Fr. S." was the worst of the worst who slipped in under the radar. We are supposed to honor the Church's heros, not her enemies.
The question we should be asking is why the sanctions rightly meeted out by Pope Pius XII against this club was reversed by Pope John XXIII! Could it be that in choosing the name "John" in seemingly obstinate opposition to the very theme he proclaimed of his own papacy, he was setting off on an abrupt change from the established course set by his predecessors of happy memory, off into the wandering in the desert that has ensued since? The question we should be asking ought to be in line with the thread: wandering in the desert is a state of necessity, the last time I checked with anyone who's been there.
Have you been there? If not, where are you coming from?
The proper sanction for heresy is major excommunication; Pius XII knew that, even if his successors often seem not to. If Fr. Schillebeeckx was a heretic, why was he not excommunicated?