Thanks for that, images would be good if you could. I'll PM my email address.
I havent drilled across the vent - couldnt see any welds there so I'll grind back the paint and see if that makes it any clearer - yes the windscreen is out , its a donor car so I'm not afraid to mess it up a bit, but I'd like to know what I'm doing as I want to do the same to my old RS and use the donor panels on it.