I am trying to figure out what type of heater I have in my '51. I see threads and pictures on air flow and recirculating heaters, but my heater does not look like any of these. It is shaped like a cube/box with the heater core laying flat at the top of the unit. The fan blows air from the base of the unit.

I took it apart to clean and paint it up. I will post pictures once I complete the rebuild. I thought I would post the description to see if anyone recognizes my description.