An easy DVD to HDD replacement process
Earlier I replaced the standard HDD with a 250GB SSD, so that left me with little room for data that I needed on my MacBook for work. Having an additional HDD solves this problem.
So, I decided to replace my DVD with a 320GB original HDD as I haven't used the DVD drive in a couple of years.
Fairly easy as the guide I used from Fixit showed me step-by-step instructions on every necessary part. Of course tracing back the steps was just scrolling back on the page. I used the Fixit repair kit that had all the necessary tools for the weird screws. Nothing was broken or lost in the process.
The battery screws didn't come off that easy because there was some dirt in them. Use the spudger to clean the screws so that the special Pentalope driver fits perfectly.
Remove any tiny broken parts and dirt while you are opening the laptop. I had tiny plastic parts broken off from the battery screw area floating around, so check that nothing is left rattling around in there.
I had to boot my Mac twice for the Disk Utility to recognize the new drive, but that might have been due to the extra drive having the OS in it as I earlier cloned it to the SSD. Works perfectly after a quick Erase procedure.
I recommend to buy the necessary screwdrivers set with the dual drive enclosure from Fixit. Mighty handy to have around for a good fit.