n0m re the L rebbe and R Shach: “I have chased down multiple first hand accounts of The Rebbe and The Rosh Yeshiva. I don’t see a personal disagreement.”
Which is why he called him part of “seridei choshech” and why if you mention Rav Shach to a Lubavicher they bristle at the fact that you’ve given him the title Rav.