Rear qtr light re-bonding

[Zippee]

Washing my 350 at the weekend and whilst cleaning the interior windows I noticed the front and top parts of my drivers side rear qtr light window have come unbonded and can be pushed out. The only thing holding it in place is the bonding at bottom and rear of the perspex. I've bought some sikaflex, any tips for doing this? I really don't want to make a mess and get this stuff everywhere. Is it possible to poke the nozzle in and just re-stick the parts that have come free?

[geoffphead]

I think its best to take whole window out and clean old stuff off to make a proper watertight seal,give Ian a bell at Track V road and confirm.That sikaflex is blooody messy when i tried to reseal my chim rear light I got it every where!