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