My MacBook was stock , 5 years old, and I ran out of space on the hard drive, had 2-3 external hard drives die on me and relied on them to free up space. Wanted to not have to worry about media storage, computer speed and quickness of operation. Couldn't afford a brand new MacBook or IMac.
Very well. Changed out the optical drive with a Samsung Pro 500g SSD first, used Carbon Copy Cloner to transfer all data from my original drive to mirror it, then rebooted the computer with the installed SSD to run the IOS. Once I knew that worked, I swapped out the original hard drive with a 2T Toshiba hard drive to store all of my media. I also swapped out the ram to get me to 8G total. Next step is to swap the battery. Printed off the Ifixit guide for my computer and followed it extensively.
I updated my IOS to El Capitan prior to the hardware swap, and backed up everything on my external hard drive before anything. I watched multiple videos on YouTube for two days prior to anything. I also had to reference the Apple help forums for many things, specifically the commands required on startup to switch drives for booting and to initiate several command prompts. I am about as average as it comes with Macs, but I did a bunch of research and homework and came out with a super MacBook Pro. The Ifixit install kit and instructions were perfect for what I wanted to do. I can use my optical drive anytime with the included attachment. Also downloaded a trim program to manage the SSD more efficiently. The Software piece is a bit more difficult than the hardware "surgery". So I highly recommend studying how to access your IOSs functions and research the appropriate software to make your system run more efficiently. Thanks!