vin says trucks a v6 ?

[67GMC3/4]

I have a 67 gmc 3/4 ton pick up that is equiped with a 327, sm420 4 speed, rockwell t221, dana 60, dana 44, the truck does not have a/c and looks simple. My question is I am the third owner and was told that the 327 came from the factory with the truck and the original owner claimed the same. so would it be possible it could have been an option ? and is there a way I can tell because when i decode the vin it says the truck is a v6, mainly just to make up my mind what direction to go with the truck.