Thanks to the info on here, i have got the power sorted on the denison and its fully installed.
The actual install is very easy, takes about 2hrs.
Simply
1 - Take Glove box out (5 bolts)
2 - Mount denison on glove box behind CD Changer
3 - Install fibre optics (Instructions are very clear on how to do this)
4 - Thread wire into glove box (USB, Ipod, and Aux)(There is already a hole but you may need to make it a bit bigger)
5 - Plug them into the dension
6 - Connect power to the CD Changer. (Red/blue wire is +ve)
7 - Turn on and test. The power must be supplied to the denison otherwise the MMI will not load up.
8 - The MMI then treats the Denison as a 6 disc CD Changer, where you can select the source (Ipod GI, Ipod UI, USB, Aux)
9 - Selecting GI enables you to control the ipod through the MMI selecting albums, artists etc as though you had a huge CD Changer! Its fantastic, well worth it.
10 - Selecting UI enables you to control the Ipod normally with sound playing out through the speakers. It doesnt display song info on the MMI though.
Overall i am very pleased with the system, alot of work has obviously been put into the construction and the user interface making it very simple to install and use.