Your drive will be a lot more than 19 hours. If you can drive the car at 60 MPH, you'll only be able to average 50 MPH with gas stops every 100 miles (and that means no eye contact with anyone).
So, that's 26 hours but your 57 has a 4.636-1 rear end so I suspect your comfortable top speed will be closer to 50-52 MPH. That means you'll average, at best, 45 MPH which means that it will take you around 30 hours.
Bill Mclaughlin
1929 Buick Roadster
Toronto to Spokane, WA