Headlight are not sealed units and if you need to open them up for repair, you will need a cardboard box large enough to fit the headlight in, and then cut a hole in the box to insert a hairdryer.
Before you start though, wash the outside of the lamp to remove the dirt from the casing.
Pop the lamp into the box, close the lid and switch on the hairdryer for a few minutes, and you will find the plastic clips securing the polycarbonate lens can now be released and the front removed to allow whatever servicing to take place
When you refit the front to the casing, no additional sealant is required, simply put the headlamp back in the box and warm up again.......you will find the original non setting mastic will reseal
Hope this helps
Brian
