sunroof not closing fully

Hi, getting new to me 98 dosco slowly sorted out. Fitted new thermostat today and as suspected there was no thermostat present. she runs much smoother at proper temp, less jerky through the gears. Front sunroof opens no problem but will only close to point whee it needs to pull down but fails to do this. I need to manually with allen key. can't find any previous thread and have tried wd40 adn greas but no joy. Anybody had this before?

I know what u mean when I close the front sunroof the is a final extra bit of movment but that never happens on my rear sunroof that just closes across the rubber seal although it's still water tight.
I rarely use the sunroofs and if I do it will be the front one. I know that there is a means of adjusting the the glass but I have never been able to find out the info on how.