Your 57 Chevy smells of gas after running it and parking it in your garage?

Either you have a leak, or, the carb is flooding over, which is common. Older cars like that do not have a pressure return hose, so, when things get hooter under the hood, as they do upon shut off, the expanding gas relieves pressure, at ther weakest point, the needle and seat in the carb, then it overflows into the motor. Make sure the motor is idling before you shut it off, and open the hood, either all the way, or halfway, after you shut it off. This will allow some heat to escape, thus reducing pressure on the line. A carb rebuild may be coming up, soon, though.