Kid in a sweet shop!

[Exos]

Ok, first and foremost hello all , new to the forums here.

I've been mulling this over for several months now and sitting in awe over autotrader, pistonheads and various other websites etc and i finally took the plunge and bought my very first BMW (X5) at the weekend; 2005 (55 Plate) E53 3.0d Sport. Came from BMW direct and was an ex BMW company car, so has had all the stamps up to about 1000 miles ago, new tyres etc etc. Looked after pretty well.

I am happy to say that i love it, its awesome!!! I love it so much that i really do feel like im like a kid in a sweet shop. Paranoia has been setting in though a little and im taking fleeting glances out the window at night just to make sure its still there lol

I've been browsing the forums the last few days and found a multitude of tips and things i didn't even know it had or could do, so much so that my head seems to be spinning with everything and I don't know where to start. Done some very minor tweaks such as Sat Nav FW >v32 and 2011 High Maps, replaced the floor/boot mats, did a diamondbrite glaze/polish.

Anyway onto some things that you guys may be able to point me in the direction of as a starter for 10 as i find my feet:

1) I want to be able to hook my iPhone (ipod) up to the head unit. Can i buy an adapter kit for the AUX output to do this, and what is the best way to achieve it (will i need any cut outs etc) and if so any recommendations over what type? most of all, is it relatively easy.

2) Xenon upgrades - There are multitudes of HID conversion kits, but again not really sure where to start, I've read about some very poor upgrades and issues with "dazzling" so do i have to do this or can i simply get some "Xenon Look" bulbs and do a direct replacement. Same for the Angel Eyes and Number Plate Bulbs? Is there anything else i need to consider here?

3) Tuning - I've been looking at units from DTUK instead of a remap, are there any other recommended manufacturers so i can do a comparison? I came across Synergy but im finding it hard to get any real write ups. Primary concern here is % increase in MPG rather than performance enhancement as i do quite a few miles per week for my job, so was just looking at a marginal increase. Computer is advising about 32Mpg currently, but on £60 of fuel (about 45 ltrs) i get about 280 miles.

4) I have some slight oxidation on the running boards so i've bought some Meguiars NXT All Metal Polish, has anyone used this? I was planning to try it out over the weekend with a little elbow grease. Alternatively i've seen T-Cut metal polish if this doesn't work. Any other suggestions?


Thanks in advance