2-3°C won't allow you to push your CPU noticeable further, if you get 20-30Mhz you would be one of the very lucky, but if you are overclocking on such a borderline with the temperatures any change in room temp, case temp etc would cause your system to crash, not very fun to have this happen to you
seriously though, a 2-3°C won't give you any advantage, even when overclocking, if you think high temperatures are holding your CPU overclock back, the next step would be water cooling, not a all-in-one small kit, but one of those larger ones from Dangerden or Swiftech, these will drop CPU temperatures considerably and you could get another few Mhz from your CPU safely (without crashes).
However in the end, CPU speed, even 100-200Mhz is not quite worth the effort imho as the increase in performance is far from linear.