All the cars in William's photos are Aurelia B50 CABRIOLETS not Convertibles.
The Aurelia Convertible is a B24. The B50 Cabriolet is a chassis bodied car. The Spider is also a B24, and costs three times the price of a Cabriolet!
To learn more about these cars look out for an article by Classic & Sportscar early in the new year, where all three are tested together.
My B50 was originally fitted with a 2000cc engine that I still have, although it is currently fitted with a B12 2266cc engine that has been bored out to almost 2400cc and fitted with a 40DCL carb that produces about 100Bhp, a useful increase over the original B50s 56Bhp 1750cc engine! .............it goes quite well.......