1964 273 ci

Hi I'm very lucky to find a site for my newly found Mopar love. I was lucky to find my 1964 barracuda in running condition..never having a Mopar before and not knowing much about it, I decided to roll up my sleeves and get my hands dirty, while I was fixing some oil leaks, I researched the engine to be a 246 casting meaning built in 1964 also a-2 at the end meaning second mold design for engine casting. However, I'm lost with the 4 barrel manifold, it shows to be a 246 casting but I read only used with 65 and 66 or did they install them on later 64's. Car does have push button automatic, I really love this car. It needs a lot of work but will be fun to do while I drive it..if anyone knows more about the manifold I would greatly appreciate the imput..thanks Sean