My lab pup was pretty ravenous too but I mostly held to the chart and she has turned out fine. Eventually she got to the point were she only eats when she is hungry so I just keep food in the dish and she isn't fat by any stretch. Then again she is only one year old.
Basically you are watching for the pups figure, they should be growing consistently. You always want to be able to feel their ribs and be able to see a defined waistline. You can modify how much you feed to control that. Also with young puppies feeding twice a day or even splitting it up to 3 times a day is recommended.
