Move your car as close to the wall as possible.
Put headlights on high beam
Mark light centre position on wall (a small piece of masking tapes works great for this)
Move car back about 4 metres or so and adjust headlights to centre of original lamp position.
Make sure you do it on high beam and also pays to have engine running to give a nice bright light (if there is such a thing with Lucas electrical systems).
Hope that helps