Water Ingress into indicator light unit

Hello all,

Have noticed over the last few weeks that my passenger side indicator unit has been more or less permanently condensed up inside to a small extent.

Whipped it off today and as expected there is water ingress into the headlight unit, I used SWMBO's hair drier to dry out the inside of the unit (from the rear, where the bulb sits) which seems to have done the trick, however where the "lens" seems to join to the front of the unit itself there is a slight edge/lip that has quite a lot of water within it, this seems to be separate from the area where the bulb is housed, as i could not get the water to run into there so i could dry it out.

Was wondering if anyone had any simialr experiences and could suggest any fixes?

The adhesive on the rubber seal on the top of the indicator unit has pretty much worn off, so was going to buy some silicon sealant to refix that into place, I had guessed that In order to sort out the issues fully i will have to remove the "glass" from the front of the unit, drain/dry everything out and then re-stick the glass back on. Will silicon sealant be suitable for this also?

The only thing that puts me off is that the glue between the unit and the "glass" still seems to be quite strong. There were no loose edges or anything that i could lift away or get any purchase of, although there is quite a bit of mould around the edge, which suggests to me that the adhesive seal is broken in places. Im guessing that some carefully applied heat and some gentle teasing with a plastic implement should get the glass off?

Cheers guys