Slow process of putting all the car back together

Finally put the door cards on, wound the window up to notice that it is leaving a 5mm gap at the top and the regulator just clicks if i try to wind it any further. I definatly went all the way before i put the panel on.

Really dont want to take my new door card off, and dont understand what the problem could be anyway..
Any suggestions ?

Thanks

note: its a '71 super as i remember the older models have a different regulator