The KV-2 formally the tier 5 king for killing most tanks in one shot is a little less fierce armor wise at tier 6. The armor is sub-par for a tier 6 heavy tank but still can bounce quite a few shots if you are not careful.
The index at the bottom of each picture describes a few abbreviations used and also the format in which the armor details are described in. Effective Armor (EA) refers to the overall effectiveness of the armor without normalization.
A KV-2 from the side is extremely vulnerable due to the lack of angles on the side of the tank. The only parts that might give you trouble are the track areas and the front part of the turret. Just fire away at the side hull armor and be careful of not hitting the purple track sections since there is no hull behind those areas. Aim towards the rear of the KV-1 to set it on fire fairly often(1-4 shots will do it).
An angled KV-2 can prove to be a difficult opponent for lower tier tanks facing a KV-2. Use the side and frontal sections for turret armor information and for the hull all of the effective armor and armor values against AP are listed in the picture. The best locations to aim are the frontal weak spots unless the KV-2 angles a lot which opens up the upper side hull armor.