[63burban]

Make sure to flush the block, heater core and radiator. I made a shroud out of two chrome half shrouds and tied them to a Speedway aluminum radiator. Make sure the fan blade is half in and half out of the shroud so it can dissipate the air/heat. Defiantly 180 thermostat. My 63 will run 180 cruising in heavy traffic at 95 degrees, never fluctuates. No ac.

My 56 Chevy Belair has vintage AC with a desert cooler 4 core and electric auxiliary fan. Several time a summer I need to blow out the fins of the radiator even with a screen behind the grill. This is one of the most overlooked things to do. Dust and dirt accumulate in the fins of the radiator and restrict the flow.
Before I installed the ac it ran fine with an aluminum flex fan an inch from the radiator, the addition of the condenser made a difference on hot days. There are days in heavy traffic when I reach down and hit the switch for the electric fan before the temp gauge rises, runs 180 with the ac on. I have no room for a shroud on this car.
Was just at Back to the 50s and had some cooling problems, when I got home I was surprised at what I blew out of the radiator and condenser with compressed air and like I said, I have a screen tied to the back of the grill which was full of bugs and debris.