The rear small side windows on the back only appeared with the 2a (approx - my 1958 Series 2 did not have them, nor did my brother's 1959 Series 2). Never run across the vertically joined sides, but sounds as if it could have been an effort at making up a lwb top from pressings intended for a swb top, possibly done at the factory - Rover did do that sort of thing!
One piece doors were, from memory, specific to the Canadian market, but of course may have found their way into other markets - I am sure that, for example, anyone in Australia who wanted them specifically could get them if they were prepared to wait.
John
John
JDNSW
1986 110 County 3.9 diesel
1970 2a 109 2.25 petrol
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