Cables required to use Samsung 840 Pro in a Mid-2011 iMac 27"?

Greetings!

I am having a bit of a challenge installing a new Samsung 840 Pro 256GB SSD. I bought this item alongside this: http://www.amazon.com/gp/product/B009GUXU52/ref=oh_details_o01_s00_i01?ie=UTF8&p sc=1

I am assuming, however, that in order to function with my iMac, I am going to need something like this: http://www.cablesondemand.com/product/CS-SATDRIVEX2/URvars/Items/Library/InfoMan age/CS-SATASERRA.htm

I was hoping someone might point me in the right direction. This is a mid-2011 27" iMac, and I am not looking to get rid of my optical drive or my current hard drive - there is another plugin on the logic board for this, but the cable I bought is not enough. Really not certain what cable I need beyond this, but I was wondering if this was right. Otherwise, I think OWC sells a custom cable, too, but I am not spending any more money or making any purchases until I can be certain this time!

If there are any questions, let me know! Thanks ahead of time for the help!