Looks to me like you have a 1963 318 Poly with a spare 4 barrel intake. You would be surprised at the parts that will interchange from the LA series. Mopar Muscle took one of these out to 432" and had a 450 HP stock looking Poly in a Belvedere. The key component to this madness was a Mopar Performance 4" stroker crank for the LA smallblock. These A engines are getting hard to find. Good score.