Alfa Romeo 6C1750 GTC by Sala
I do not have any photos in the computer at this time but I can direct you to a few potential references. I can scan some of them later if it should become necessary.
I also have to admit that I have no personal knowledge of either of the two following cars.
AR6C101014883 has been labeled as "Stabilimenti Farina" as well as "Sala". A photo of this car appeared in a periodical of limited duration called Storia Illustrata dell'Auto Italiana dated 21.4.1962 on page 275. My notes indicate that "Continental Pictures" and "Sala" are mentioned. I believe I have this in my small library and will check when I next get to spend some time there. There is another photo (or perhaps the same photo as I'm not certain I checked this detail) in the Italian encyclopedia, Milleruote, Volume 5 (page 174). My notes indicate it is captioned "Stabilimenti Farina" here. I have listed this car in my files as "Stabilimenti Farina" in the past and have been corrected by one knowledgeable friend ... who is not infallible, so I really cannot be certain.
AR6C101014925 has not had any controversy so far as I am aware about the coachbuilder but once again I have no personal knowledge. A photo appears in Angela Cherrett's excellent book about the Alfa Romeo 6C1500-1750-1900 on page 99. A photo also appeared in Hemmings Motor News, September 1992 (page 6816) in an advertisement for the Kruse Auction held at Auburn, Indiana - September 6, 1992. Unfortunately, my father's collection of Hemmings was discarded when I was not looking so I do not have this reference ... unless it is copied into my files ... which I will check when I get to them.
One thing that may help determine the coachbuilder for these cars with some sense of certainty (?) is finding the coachbuilder number. It seems that both Stabilimenti Farina and Sala had their own numbering systems. I am not certain about Sala as I've found only one car (from 1909) that seemed to have what appeared to be a body number. Who knows what they were doing by 1932/1933? So, any study of this characteristic wil require inspecting a few cars to know for sure what we are looking at.