I've seen them in the past more in American bike mags of that era, they do look quite good.
As far as I can remember they had a bespoke cast alloy manifold to mount them to but other than that it must just be setup as I know you can change the venturi size for your specific application. They are also normally mounted with a o-ring type seal and clamped with a thackery? type washer to avoid transmitting engine vibrations to the carbs as I understand it.
Haynes, you live in the right area to see rally stages I guess, I've spent many an hour years ago watching rally cars in Welsh forests.
Wolfeze, those talbots were quite a quick car and handled well too, I navigated on a couple of tarmac rally events in one some time ago.