After more and more research, I am becoming worried that the case I picked out http://www.newegg.com/product/prod [...] 6811146027 wont house the heat sink that I picked out http://www.newegg.com/product/prod [...] 6835233003 once the CPU is mounted onto the mother board. The case is 215mm wide (8.6 x 25) and the heat sink is 120mm wide. With the posts for the mother board, the thickness of the board itself, and the CPU it looks like it will be pretty tight squeeze to fit this in. Any comments or ideas as to if it should fit?

The  HDT-S1283 is known to fit in the Antec 900 case which is 8.1" wide and your case is 8.6" wide.  I think you can relax.

Cooler specs 120(W) x 50(H) x 159(D)mm
Case specs : DIMENSIONS (W x H x D) 218X438X536 mm.
That's 59mm of clearance. +1 for what WR2 said.