170 or 225?

That's a very old myth, and it is not correct. Carter BBS and Holley 1920 carbs were both factory-installed on 170s and 225s in most years between 1962 and 1969 (pre-'62 only BBSs). Moreover, the car in question is roughly half a century old; plenty of time for plenty of carb-swapping.
My 1963 service manual show only holley carbs used on 225s the bbs was used on 170s and 225s the picture shows a holley carb as the fuel line is entering the carb on the left a bbs enters the carb from the front. The car appears to be a 66 and a California emission's because of the air cleaner and the vacuum controls at the right rear of the engine. Anyone with a 66 service manual that can confirm that in 66 They used holleys on 225s? The gentleman asked a simple question with only the picture to go on. And yes I agree that a 53 year old car could have anything under the hood.