Hey everyone. Just found this cool video guide showing how to install a 2nd HDD/SSD to your old macbook pro. It looks pretty simple by just replacing your optical drive (lets face it - who uses those anymore) with a 2nd SSD/HDD. I think i'm gonna try this to see if it will host my macs performance by installing a second storage device. Probably gonna go with a SSD. Looking forward to having a boot-time of 20 sec again 
https://www.youtube.com/watch?v=-ldJhwwwe3I
/Martin
https://www.youtube.com/watch?v=-ldJhwwwe3I
/Martin