When the Heilige Beis Yisrael ztz"l first became the Gerrer Rebbe [in 1948], he used to spend 3 hours on Erev Shabbos learning Kabbala privately with Rav Charlap ztz"l in Rav Charlap's apartment in Shaarei Chesed.
[Pe'er Yisrael Page 317]
When the Imrei Emes passed away and the Beis Yisrael wasn't sure if he should become the Rebbe, Rav Charlap sent him a note hinting to him that he should accept the yoke of leadership, as he ultimately did.
[Page 270]
The Beis Yisrael's talmid, Mori V'Rabi Kvod Kedushas Ha-Admor Mi-Tolna Shlita, suggested to a person I know well that he read the biography of Rav Charlap Shirat Ha-Yam. I pass on the עצה טובה.