Window now removed :-)
o Sill provided leverage/bracing without much effort
o Older flat-blade screwdriver with a nut part way up it

That and some heat-cycling with torch & flick easing oil :-)

Now the fun - getting screws out of the window itself!
o They've seen a bit of surface corrosion
---- perhaps enough to "stick screw & hinge into one"
o So more heat & flick easing oil
---- very narrow slots on these screws

Going to use the 2.5" hinge - but with stainless screws.
That should stop the screw-to-hinge welding at least.

Moral: open your windows regularly.
--
Dorothy Bradbury