looks like you got a pretty nice fan set up already, and that fan you picked up is pretty nice too. but if ya wanna fit a 92mmx83mm(lets just round up) fan in there, you may have an issue with it fitting in the available space. (I'm assuming were on the same page) If you want/need it in the back of the case, but don't have a wide enough case or fan slot, you could
A: Dremel out the fan grill so it fits
or B: If the above won't work, you could put a tunnel of some sort on it and mount it farther inside the case where you have more room.
liek so (sorta)
you could prolly use screws or somethin similar for the supports. you may have to make your own holes though, but thats no big deal.
keep in mind that your post was a little confusing to us non-morning people like me, so if I'm way off topic, my bad...my bad...