Sorry to report that the misting Headlights have returned !!.
Water in the headlight almost sloshing around.
No way that amount of water could be condensation, there has to be a leak !.
Headlight out of the car - - again.
Took it apart, the large Gasket at the rear of the case was wet through !.
The Gasket looks like Rubber, BUT, it is porous, and soaks up water like a sponge.
The water gets in where the two halves of the case fit together and are clamped into the Gasket by the Clips.
IF, the Gasket was NOT porous this would OK, but the water passes through the gasket into the rear of the case.
When the lights are switched on, the heat from them causes condensation on the inside of the Lenses.
Warm and wet inside, colder outside = misted up Headlights.
With the wet gasket out of the case, I laid it on some paper tissues, and rolled a small bottle along it to remove the water.
Hung it out to dry for a few hours.
While it was drying, cleaned all the water out of the light case, making sure that ALL of it was out.
Fitted the dry gasket back into the case, built the case back together, checked everything was correct
On the outside of the Case where the two halves meet, I sealed the small gaps with Black Silicon Sealer, ALL ROUND, dont miss any small gaps.
This was to prevent any water getting in and onto the Gasket, which would allow the water into the case again !.
Now that I know where the water is coming from, and how it gets in, maybe the Silica Gel will not be needed any more !!.