two amusing things about this
(1) +Kirk is practically telling ~Spock straight up that he needs to kill ~Kirk (or, at the very least, absolutely does not give a shit about ~Kirk's survival). I mean, how else does one get at the device in ~Kirk's quarters and take over the ship?
(to be sure, we see from the +universe scenes that ~Kirk is a useless animal who is completely untrustworthy, but +KIrk, at best, has only circumstantial evidence for this...)
(2) given the ~future we find out about in TNG/DS9, it seems this was the Worst Timing Possible for a revolution.