Hi forum,
Welcome!
I just bought a Mk5 GT TDI 2.0 3dr black with Grand Prix 17in wheels (2004).
Nice car!
I would like to make the following mods (yep, I don't even own it yet :-)
Rear LED lights
Hmmm, you may have issues with the ECU and CAN-BUS coding. The standard Golf V rear lights use mini 6W halogens (rather than the conventional 5W & 21W tungstens), and the intensity, or brightness is ECU controled, so a straight swap for LED tails would cause DIS error messages (even if you are able to get them to work properly!).
Xenon front lights
As 2007GTI stated, they are highly illegal. They would also void your insurance - so don't do it!
By all means, swap the standard H7s for upgraded H7s, like the Philips Vision Plus 50%, or if you like the "Chav" look, then any of the "blue" H7s, but don't try the pukka HIDs!
Sat NAV
Phone kit
Both those have been done with success.
I am not the sort of person who is going to have much success trying to fit any of that stuff myself.
Can anyone suggest someone in Cheshire who will do the job right at the right price and give me an idea of what I am likely to pay?
If you are near Liverpool, then search for username "Doc", and PM him.