[randy500]

Post a picture of the pedal under the dash where the booster mounts.
Do what B.W. states in post 3, the push rod that exits the master cylinder should just barely touch the master cylinder when at rest.

Does the pedal return when stuck down if you remove the vacuum line? If so the booster is bad.

There is no way you had the vacuum line hooked up wrong at the carb unless someone used a bunch of adapters to hook up to one of the small vacuum ports like the one to the distributor, most boosters connect to the lower rear of the carb.

Did you change the master cylinder too?
Post a picture of the vacuum connection and booster too.