injectors are easily accessible on the TD. all you need to do is remove the supply lines on right hand side of injection pump (spanner), then you can remove the fuel lines from the injectors (spanner), then the injectors can be removed (socket on ratchet).
if you're very careful you could probably get away with leaving the fuel lines connected to the pump, and just remove them from the injectors, but dont bend them too much or they will kink and leak.