The earlier 12v glow plugs don't use a controller like the 5v glow plugs - they use a simple relay (on-off). If you can see the glow module on the left side of the block under the intake manifold, you have the 5v glow plugs.
It seems that swirl flaps were only fitted to the M57D30TÜ fitted to the E53 in markets requiring Euro 4 emission specs at the time (I think that is right -
Clavurion will know more!
) - i.e. Switzerland and some other Euro markets. Pretty sure that the UK, Australia and NZ markets got the Euro 3 spec cars, with no DPF or swirl flaps - but it's easy to check for them. Use a small inspection mirror to check for the swirl flap actuator rod on the underside of the intake manifold.
I doubt you will find them to be fitted but from what you have said about your particular car, I guess it's possible.
