I have just successfully replaced the bulb in a Sagem hd45.
First make sure its the correct bulb.
Remove the housing containing the bulb as described in the USER manual.
Note how the retaining spring, which holds the bulb, is fitted.
Remove the old bulb from the plastic housing-BUT- first disconnect the cables and leave them in place.
The new bulb comes with cables installed and a spare glass fuse which must replace the (blown)one at the top of the bulb case.
Remove the cables from the new bulb and fit the new bulb into the plastic bulb container and fit the retaining spring.
Connect the old cables to the new bulb.
Fit the bulb (do not touch the front of the bulb) in its container to the TV as specified in the users manual.
If you try to remove the old cables from the plastic bulb holder you will probably break if where the two pin plug is. If you do, you can fiddle the plug into the appropriate socket inside the TV as the bulb container is slid in. But its easier I think to keep the old cables in the bulb container.
Jacko
July 2009