It could approach from the south - but the maps they released at the time, looked more like approaching Lucien L'allier (or possibly Central Station) from the west. Which could allow them to build new platforms and track, in a more northerly direction under the existing track (and platforms?) (the current Central Station platforms are more northwest to southeast rather than north-to-south. I'd have to take out a protractor, but they almost look closer to east-west than north-south!
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