I performed this replacement with the ENELOOP AAA rechargeable batteries.

Notes, scuffing up the terminals on the batteries was necessary to get good adherence of the solder.

I found good results with using the needlenose pliers to gently and slowly (s o s l o w l y) pry away the terminal connectors. They're not soldered to start, so it's a little weird. Then I had to smash down the bent up terminals to make them flat again. I imagine that this battery replacement will only be possible a couple times before that metal eventually fails.

Don't be too startled when you're putting it back together and you accidentally turn the thing on. Startling! :) But harmless.

Good luck all! Thanks for the guide!

The additional PDF file with the screw and part pieces was BEAUTIFUL - every guide should include it! So helpful!

I'd like to add that the part you buy from IFixIT has some blue tape like stuff which has to be removed when you install the parts. This is not noted in the guide.

When you try and insert the new part (assembly) the mic may prevent you from sliding the assembly in, until you realize that the mic needs to BEND a little - to a 90 degree angle, before the assembly will fit.

Did I bork my connector? http://imgur.com/a/iqX5I - after reading these comments on reconnecting, I think I'm just eye fatigued, but I can't get that %#*@ connector back on there again....

I did this with the iFixit provided 1TB SSD. It all went well. It's really an easy task, though it might seem daunting. Just don't "force it" with any of the delicate parts.

The restart of the computer was a little startling. I flipped open the laptop and bam, it started. Might have been an errant press on the power button.

Also, to reinstall, I used "Internet recovery" which worked perfectly, as building a thumb drive boot drive failed on me. Internet recovery saved my world. Took about 4 hours to restore 320G of data on my new drive.