The 2300 series is a continuation of the Italian type 102 "2000" that was produced from 1957 through 1961, and replaced by the 2600. The type 102 was an evolution of the 1900 made from after WW2 through the late 50's.
When Alfa ceased making the 2000 in 1961 they sold the tooling to FNM in Brazil, who started making a duplicate of the 2000 Sedan (not really called a Berlina at that point). It was essentially identical to the 2000 made in Italy through 1961, using the "cast iron" 2000 cc engine.
FNM then began making changes, increasing the displacement to 2150 by using a longer stroke crank, and then 2300 by increasing the bore, which required changing the bored cylinders to wet-sleeves within the cast-iron crankcase. Externally, the 2150 and 2300 engines look much like the original 2000, with subtle casting changes. I was able to bolt-in a 2300 into my 1959 2000 Roadster making only a small change to the throwout bearing system to utilize the more modern diaphragm clutch used on the late model 2300's.
The chassis of the 2000 was largely continued into the 2150 and 2300 models, with gradual changes such as ball joints instead of king-pins, disk brakes instead of drum, dual master cylinder, power steering, etc. There is a fair amount of retro-fitability if one wanted to use the later parts on the early Italian 2000's, but that would probably be more trouble than it is worth, as getting parts shipped up from Brazil is expensive and logistically challenging. Not impossible, just difficult.
The last versions looked a lot like the contemporaneous Italian "Alfetta" sedan series, but there was not much under the skin that matched.
Given Brazil's internal economy and political climate, some of the Alfa/FNM cars were made to use alcohol fuel. Current cars in Brazil are largely equipped to use either gasoline or alcohol, which I guess is easier using fuel injection. Some of the early FNM engines faced very low octane fuel, so the compression ratio was decreased from the Italian spec. The later engines were back up to around 9 to 1, or slightly more, partly because Brazilian fuel had improved as well as the failed effort to export these cars to Europe.
I've looked at pics of high-spec 2300's that are very nicely equipped, with leather, power steering, AC, etc. I'd like to have one, but doubt I could get one up here without a great deal of expense and hassle.