Kansas;I have Vintage Air in my 56 Customline with the condenser mounted 2" in front of the radiator core. I looked at the possibility of installing a pusher fan in front of the condenser because the motor would run hot if I was stuck in traffic or in a parade, but it was just fine crusing down the road. The problem for me was the lower splash apron support bracket between the back of the grill and front of the condenser which gave me 3" or less of space to the front of the condenser. My radiator core is about 19" x 19" so I was looking at 16" fans all of which were more than 3" thick. Most were 4" thick. You might find a low profile fan less than 3" thick, but you would have to go way down in diameter.
Thunderbirds Southwest just came out with a 55-56 Ford car 2 piece fan shroud that I am considering, but they are not cheap...$169.00 plus shipping.
Rono