So maybe a year ago, I had a friend that needed his iPhone's screen replaced. Well, in doing so, I had damaged one of the key components on his phone. A while later, after replacing it, I had an iPhone with a connector that basically looked like this:

Naturally, I thought, this phone is fucked. Anyway, fast forward to a few weeks later... I had found a source for this connector piece, and it was cheap enough to order, so I thought, "What do I have to lose?"
Well, the piece came, and I brought everything into my work, and this is where it all began. So here is the basic run down of how I do the repair. After disassembling the phone with the tools below, I start removing the remaining pieces of the old connector with some fine point tweezers.

Thereafter, I remove each and every pin that remains soldered to the board CAREFULLY without lifting any solder pads (this is a big mistake many inexperienced repair guys do). Once the pins are free and the solder pads are clean, the area is cleaned up with some 99% Isopropyl Alcohol.
The procedure to solder the new connector on takes some fine articulation, steady hands, and a VERY fine tip soldering iron. If there is anyone out there that wants to do this themselves, please be aware that my iron tip is .008" in size, the smallest you'd ever find anywhere. You cannot buy this at RadioShack haha! It helps that I have all these cool tools at work. So once I position the new connector, it is all done by reflowing the existing solder and adding solder in places necessary to prevent melting the new connector.
If you take a look at the before and after pictures of a customer's phone I've done you will see that I barely used any new solder to secure the connector. Also, for those DIY guys and gals, please note that I am doing all this under a stereozoom microscope with a 5x zoom, it absolutely cannot be done with the naked eye, magnifying glass, or anything other than the microscope!

Even the soldering station I use is a special type, that allows temperature control, radio station buttons for different temperatures, and the tiny chisel tip that is almost like a needle point.

So here are the results of the hard work! These are before and after pictures of a customer's phone. He had sent me the phone in the condition the first pic shows, and after I had cleaned it up and performed the repair, I took the second. Both were taken with a powerful Nikon inspection microscope.
BEFORE
AFTER
I've found a source to purchase these connectors in bulk, and am offering my service throughout the forums (username is krazy or my full name):
http://modmyi.com/forums/hardware/691164-broke-connector-3-locking-mechanism.htmlHere is a customer that did a review of my work for me:
http://www.pnosker.com/reviews/35-ireviews/65-iphone-connector-repair-review-hector-truongSo if you're looking for someone to repair your #3 connector, also known as the earpiece/proximity sensor connector, I'm your guy. I've done over 50+ phones and I provide the connector for you. Email me for more questions!
hectordtruong@gmail.com