There basically are three Series Windscreens, not surprisingly Series 1, Series 2/2a, Series 3, and none are interchangeable. Series 1 is rectangular, Series 2/2a and 3 taper towards the top and have identical dimensions but totally different hinges. As far as I know all are the same height.
Series 2/2a windscreens changed in 1967 when the wipers moved from the windscreen to the bulkhead so later ones do not have the holes for the wiper spindles, but they are interchangeable provided you either block the holes or drill them as necessary.
The glass is identical in Series 2/2a/3.
For completeness the 90/110/Defender is different again, with different hinges and is higher, although the width and taper are the same as the 2/2a/3 and of course it is one piece.
Also note that most existing Series windscreens will be toughened glass rather than laminated, although laminated ones are readily available.
John
John
JDNSW
1986 110 County 3.9 diesel
1970 2a 109 2.25 petrol
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