Since you are going to replace the original fan with an electric, this is a moot point, however, itīs not necessary to remove the radiator to remove the fan (maybe so to install an electric assembly).

The metal strip you found, which pops back and forth from temperature change - which looks severely bent and thus its falling out - is a thermostat. When the engine is cold the fan runs constantly. After the engine along with the metal strip gets warm, the metal strip bends slightly and pushes on the pin behind it, which allows the oil in the chamber to flow, allowing it to now control the function the fan by RPM.

Unfortunately, I donīt think you are going to find an electric fan with the longevity that a mechanical fan has. If this were the case, you could wire the aux fan to run at specific temperatures.

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