Another i7 question

[Domepiece]

Yes yet another i7 920 OC question. So im at 3.7 vcore 1.281. Dram voltage at 1.64. QPI at 1.35. temps are getting to 70C, 67c,66c,63c. I am running thermalright ultra 120 with scythe s-flex lapped. So the questions are
A. Are the difference in temps from core0 to core3 normal?
B. The ultra seemed to twist some when i was installing is this a cause for concern and will it effect my temps much? using AS3 cuz i had leftover from another build.
C. Have all set in antec twelve with ultra fan blowing out the 200mm. Is this a proper setup or should it be blowing out the back?

 

[Proximon]

Why would the cooler twist? Are you using the bolt-through kit?

The variation in cores isn't huge, but it does make me wonder if the cooler is really seated right.

 

[Domepiece]

Basically i went to align the screws and it would move on me til i got 2/4 in...i read its happened to other people but no good answers as to whether or not it effects temps...