Single to dual E5-2660 CPU in a 5600

Hi,

A couple of questions about installing a second CPU.

I have a single E5-2660 CPU (2.2ghz 8 core, 16 threads) in a 5600 and i'd like to put another in. I'll need both a cpu and heatsink. The current power supply is a 825w and I also have a GTX 1060 OC 120w, 32gb ram and ssd.

I need the machine specifically to run one particular photogrammetry package that apparently uses all the cores it can get, specifically uses GPU for point cloud processing and takes advantage of Nvidia CUDA instruction where possible. I will however be reverting to CAD and video editing once this point cloud job is done.  

For example for budget reasons If I want to put in another E5-2660 cpu, which has got 8 core and 16 threads how do I find out what particular CPU version to install?

Also what is the correct model of heatsink?

Thanks