I honestly can't say I "saw" the conversion but ... I did drive a Berlina so equipped.
This was many years ago; a used car lot “tire-kicking” moment. My recollection is that while an improvement over the column shift and its accompanying vagueness, it was not as crisp as a Spider floor shift.
Thanks for posting the ad; I always wondered how they converted that car.
Good catch, Greig. I notice that the ad does not mention the bizarre reverse-H shift pattern! BTW, the shifter that I have feels clean and precise, with a nice short throw, though stiffer than the factory shifter. This is off the car, of course. The real test will come when the car is running.