Simple repair — same here, left the battery alone. Just a couple FYI's for your next steps after the new hard drive is in. (This might be obvious, but I overlooked it.) I forgot to format my new drive and I wasted a few hours accidentally installing OS X on a different partition of my boot drive.
1. Once the new drive is in and your OS X boot drive presents you with installation instructions, go to "Disk Utility" first.
2. You'll see a list of drives: your new drive (congrats you installed it correctly!) as well as your boot drive
3. Select your new drive (top-most level) and click into the "Erase" options
4. Make sure you select "Mac OS X Journaled" and leave the name "Untitled" (I think these are the defaults)
5. Click "Erase"
6. Exit "Disk Utility" and install as normal. Make you select your new drive "Untitled" to install to :)
When assembling the new display, I felt like this was the hardest step. I was never sure if the cable was secure, and messing with that little lock was scary. But, all worked!
Re: difficult antenna attachment — Sliding pressure from left to right, instead of straight down, seemed helpful. Although, I may have gotten lucky after trying to attach for about 30 minutes (!!!). Loosening the 2.9 mm screw holding the bracket seemed to better my chances for sure. Thanks!