As DDY says you don't really need to change the northbridge cooler unless you are heavily overclocking, I decided that for the £10 it cost to change it over I would rather have lower temps as it was getting quite hot.
Since you have a Q6600 (266MHz FSB) you will not be overclocking the northbridge until the CPU is at 3GHz anyway with my 333MHz FSB chip I was OCing the northbridge from the start.
As to the Scythe Mine you will fit it no problem at all
If you want more pictures then shout and I will take some, worth noting that my Hard drives are mounted backwards so the cables come in from the front of the case makes it neater for the cabling
but that required a bit of modification i.e. I cut a hole in front of the drive cage to pass the cables through