Okay, so the correct HD and RAM have both arrived, I've looked at the ifixit guides (and will soon watch the OWC videos), and think that I'm ready to do this. I just wanted to check with you all again to make sure my plan makes sense. And again, I apologize if this is elementary -- never done this before.
1) Back up current HD (just let Time Machine run as normal) onto my external HD.
2) Open the computer and replace HD.
3) With computer still open, replace RAM. Close computer.
4) Install OSX on the new HD from a CD.
5) Once OSX is installed, load from my Time Machine backup using Migration Assistant.
Sound good? Any tips? Appreciate the advice, thanks.