Aside from this sicha, where the Rebbe says that Chassidim should be bound to the Rebbe in all levels of the Neshama, this has to be the most powerful statement I’ve seen concerning the extent of devotion demanded from Chabad Chassidim to the Rebbe:
We find ourselves in the Shabbos that blesses the month of Shevat, including and especially the tenth of Shevat. Thus everyone should undertake to increase with additional vigor to [devote himself to] the “deeds, teachings, and service” of the one whose Hillula  we are commemorating, my father-in-law, the Nasi [leader] of the Generation, “who instructed us in his ways, and we will go in his paths forever and ever.”
In particular one should increase by nullifying oneself and bonding totally with the Nasi of the Generation, [to the point that] “The Nasi is everything” [in one’s personal life—i.e.] for every single person, his existence and all aspects of his life, in every single possible area [in the Hebrew, “bakol, mikol, kol”], are consecrated to the Nasi of the Generation.
This is accomplished by filling and permeating them [all aspects of one’s life] with fulfillment of the mission assigned by the Nasi of the Generation, who is the Moshe Rabeinu of the generation, [of whom it is written, “the first redeemer is the final redeemer,” whose main role is “to bring the days of Moshiach” in actuality.
Sefer HaSichos 5752, Vol. 1, p. 266.
 Tanya, Igeres HaKodesh sec. 27.
 The yahrtzeit of one who taught the inner dimension of Torah. This is considered a joyous occasion.
 Tanya ibid.
 Rashi, Bamidbar 21:21.
 “There is an extension of Moshe in every single generation” (Tikkunei Zohar sec. 469). “There is no generation that lacks one comparable to Moshe” (Bereishis Rabba 56:7).
 See Shemos Rabba 2:4. Zohar 1:253a. Likkutei Sichos, Vol. 11, p. 8 ff.
 Mishnah, end ch. 1 of Berachos.
In my own words: Although the Rebbe would always speak of the Previous Rebbe as the Nasi of the Generation, Chassidim know that whatever the explanation for that may be (and I hope to devote a post to this topic im yirtzeh Hashem, but seemingly one of the main explanations of this can be found here), since the Rebbe openly accepted leadership on Yud Shevat of 5711, the Rebbe is the continuation and successor of the Previous Rebbe. Therefore whatever the Rebbe says about the Previous Rebbe, we translate for ourselves as teaching us about our relationship with the Rebbe. The Rebbe certainly knows that this is how Chassidim will relate to his words, and thus this was clearly his intention.
Thus, the Rebbe is in effect telling us in a very humble way that the day of Yud Shevat should bring us to devote ourselves totally to the Rebbe, in every single aspect of our lives, by bringing them to be totally permeated with one goal, the goal of the Rebbe—to bring Moshiach NOW.