Sorry for the delay getting back to you, my friend didnt bring the device in until yesterday...
I can confirm that it is a Kindle Fire 2nd Gen (Otter2), and it is running 10.4.6 firmware/baseband...
I tried to root it in work, on my Windows 8.1 and Windows 7 based PCs, and unfortunately it wasn't detecting it, or working with the ADB drivers....
I tried at home on my Windows XP and Vista setup, and again wasn't detecting it. However it did detect on my Windows 7 setup at home (triple boot). This must of been the partition I used for my friends one many months ago... (although I found various Kindle related files on each partition).
Anyway, I got the damn thing rooted now, thankfully... and shall move onto the 2nd Bootloader thing... However, is there any other way, or easy way of doing this other than whats in that post?? I don't mind doing it, and will follow it again. However late last night I was losing the will to live as it was hard work getting to do things... (compared to other Android devices that are a breeze to do...).
I tried to backup my partitions on the Kindle what it says to do at the start, and it kept saying it couldnt find these on the Kindle... I read in the guide that it said I could download them from a website, but all I could see was scripts and not backup partitions... Is it really important to backup my own ones, or could I just download someone else's Kindle Fire 2nd (8Gb) model??
And yeah, is there any other way to get custom recovery / rom on, other than the original guide...?? - not gonna give up, just last night kept falling asleep trying to follow it... when things werent working and patiently waiting for things to happen/work... lol
Anyway, thanks so much for replying to my question, and for all the help you have given me to get me started... much appreciated!!