After using the search I realize how dumb I am for replacing my bulbs without replacing my wiring harnesses, but the fact remains that I put in some hyped up xenon blue bulbs only to notice that one was out a few months later. Upon closer inspection the bulb is completely fine but the socket (I guess that's called the harness?) is all messed up. I checked the working one and it's just a little messed up. My question is what do I buy to fix the problem?

I looked around and I think it's this: http://www.eautoworks.com/html/ORD-1-1-1-4671.cfm (the 9007 one)

If that's what I should get how hard is it to install?
If that's totally wrong what should I do?

I assume the melted connector is the problem because everyone of my bulbs works fine except that one, and that one was dim for a while before it went out completely, like it was not getting enough contact or something