Gvif connected to CAN wiring

I have 2 questions if anyone could assist

1. I know that hids4u say in the installation that you dont need to connect
The gvif interface to the CAN wiring, but i was wondering what
Difference does it make if connected as other installation instructions
Show it to be connected ( http://www.gsmserver.com/content_file/prod..._v6_xx.PDF )

2. The Installation also stated to connect the gvif to the sat nav dvd
Iv seen instructions showing you can connect to behind touch screen aswell
( http://www.gsmserver.com/content_file/prod...ouch_1.PDF )
Does this make a difference? I.e will i not then not need to switch to sat nav
To have gvif on, will i be able to acess gvif from any menu having pressed the toggle button?

Thks   Range rover td6 54 reg touch screen

I think Hids4 you are just playing safe alot of forum members are well meaning but we all know what happens when the sht hits the fan.
Anyway connected a unit to the can on a sport at the weekend followed instrutions worked flawlessly.
Pionts to watch,all work keys out of ignition, keys out of car
spring any door locks so the car thinks everything is closed,once interior lamps go out
AV units go to sleep between 5 /10 mins
if you are really concerned wait 30 mins at this piont most circuits are in sleep mode
here you are only soldering to the can wires in parallel, do one at a time
If for any reason you have can wires that are going to loop through do not under any circumstances cut 2 or more at the same time.
hope this helps broncoupe

Thks for your reply... What did you connect to the can bus? Range rover td6 54 reg touch screen

One of those units doing another on a Discovery 3 this weekend
regards