Yesterday I fitted an 07 larger tank to my 05 bike. The bike starts and runs but I noticed the 07 tank has the cable underneath as per the below pic whereas my original 05 doesn't.

Can any one tell what this is for?

Fuel level .....not needed if you have used the 05 pump as the level indicator is within the pump

Ah ok, I left the tank with the 07 pump in. I guess I'm going to have to put the 05 pump in nevermind.

Hi
just put a 2007 tank on my 2005 SD. But put an 2008 pump in mine as my 2005 pump was playing silly buggers. So had to get a low fuel switch and re-wire it.
2005 wiring loom has the following wires going to the pump, has a red, a blue and a black wires going to the pump. The wires coming from a later model pumps have the same colours and plug.
The external low fuel switch has a orange and a black wire coming from it.
Simply join the blue and orange wires together, fuel pump side of the plug.
Joint the black wire coming from the low fuel switch to the black wire coming from the pump together, fuel pump side of the plug.(its a common negative)
Doing the wiring joins pump side of the plug enables you to disconnect the tank and remove it as one.
I hope this helps those in need
Steve