Wire Harness advice/help

I am looking for easiest way to replace my under dash wire harness and found the one in the link below.

Does this one need anything other than just plugging in? I cannot compare the pic to the actual very well, and wanted to know if others bought this one and how did it go?

http://www.classicindustries.com/product/mopar/a-body-dart-1963-76/parts/ma2314.html
thanks in advance!