If you have 4.82 or 4.82 han installed.............follow the video, you install 4.84 or 4.86 Hen Firmware Two Times in a row, from a usb stick.............then you go to the website from the ps3 just like in the video, and install the applications from there.
It should wipe or mess up your games, but, its a rare possibility that you would need to reinstall everything, nothing to worry about.
EDIT
The website that provides the applications you need to use doesn't support 4.82 firmware anymore, if you don't already have a hdd with that on it, you have no choice really but to upgrade. If you have the choice choose the lowest firmware to upgrade to like 4.84, double check that that is the most stable.
It was a bad decision to remove 4.82 han, it was very stable.............anyway. You can have multiple harddrives, you just need to re-install 4.84 hen or 4.86 hen, each time and the applications from the website on it, since they are saved to each hdd separately.