The thing that is most important to clean here is the screw in the bottom. It has holes which, if clogged, will prevent your engine from running for more than a second or two. Make sure you clean them out with carburetor cleaner. It's easy to miss, as it falls out into the socket when it's unscrewed.

Make sure you empty the fuel, remove the fuel tank, or clamp the fuel line before you do this step, or you'll get fuel everywhere!

My replacement power supply did not come with an Ambient Light Sensor. I thought I had gotten the wrong one, but in fact the ALS comes easily off the old power supply (using a small flathead screwdriver to pry it off) and attaches to the new one.

Don't forget to spread the brackets on the sides apart to release the chips.

I'm not sure what the point is for this step. This helped not at all in getting the drive out. Also, the cable is taped down, and must be untaped before the card will come out.

It's best, when putting in the new drive, to screw the bumpers into the right side of the drive, then put the bumpers into the holes on the left side. Then, put the drive in in the reverse way you took it out: Left side first, then shove the bumpers into the holes on the right side. It's difficult, but it's the only way I could make it work. Then, of course, screw the left bumpers in the same way you unscrewed them.