I tried dropping the window and although no slider dropped out of the channel, I still couldn't access the screws. So I had to remove the glass.
For me there was still too much force to be exerted to try and push the rear slider out past the metal header strip - even after loosening the track.
So I also had to drill out 2 rivets from this strip to bend it out of the way and let the slider past:
P1010878.jpg
I prefer drilling these two rivets to forcing the fibreglass out of place, and given the small additional effort to remove the window completely compared to dropping it, which means you can then clean and re-lubricate the tracks & sliders, I think its a better way to do the job all-in-all - because once the glass is out you have much better access to the weatherstrip screws themselves - meaning if they are corroded you've got a better chance of getting enough outwards force on them to prevent the screwdriver slipping - drilling them out is not too much of a problem as they are in fibreglass but to do it well you'd need longer drill bits than I had.
But was I missing something? Does that strip have to be displaced to get the rear slider past? Or should I/could I have forced it? When I put it back together I'll probably re-rivet it or glue it.
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