The glow plug is fitted to the inlet manifold screwed in from the back side next to the rubber hose which connects the pipe from the air filter to the inlet manifold there is a fuel pipe and an electrical terminal pushed on to it, you need to swing the battery out to gain access, check there is power getting to the electrical terminal with a multi meter when the ignition switch is held at the heat position, You need a 15/16" AF spanner to change it.
Para Handy, December 2009