I have emailed the replacement for VOSA for some definitive answers and in the usual fashion, received a computer generated reply saying that due to pressure of enquiries at this time it may be some weeks before I get a proper reply.
Turning to the question of who designed the 275GTB, there are conflicting answers in today's literature (due to repeating old disinformation?) but I can point you to
http://everything.explained.today/Ferrari_275/ where they have some good info.
For me, the clinching point is that Pinin Farina was at that time a personal friend of Enzo Ferrari, whereas Scaglietti was the contracted body constructor. Farina designed and built the (ugly) 275GTS of which less than 200 were sold whereas about 970 of the 275GTB were built by Scaglietti in various street and racing variations. When Luigi Chinetti, the US importer, asked Ferrari for a soft top version his request was refused but eventually a run of 10 was sanctioned and Scaglietti built them all.