[19Fordy]

You may have to remove the steering wheel, drop the column from the dash then unbolt the steering box from the frame, raise the front of the car and pull the entire assembly down and out thru the firewall/ floorboard. That's how I did it on a 51 mercury.
Here's what the 49-51 Mercury manual says: I bet Ford is similar. No need to drop the A-arm.
1. Remove pitman arm from steering box using a puller. 2. Remove steering wheel. 3.Remove necessary floor covering to make possible the removal of the steering column to dash cover plates. 4. Remove steering column to dash cover plates at base of steering column and firewall. 5. Disconnect steering column electrical connections. 6. Remove cotter pins and release shift rods from steering column shift levers. 7. Release U-bolt and steering column bracket from dash. 8. Loosen steering column clamp at steering gear housing. 9. Loosen 3 bolts securing steering box to side rail. 10.Remove woodruff key, spring and steering column upper bearing sleeve 11. Slide steering column tube from steering shaft. 12. Remove the 3 bolts securing steering box to frame side rail and remove assembly from bottom of car. My NOTE: If you have a lift it's a lot easier as the front of the car must be raised high enough to remove steering box with shaft from bottom of vehicle.