From
https://www.us-lighthouses.com/faq.php
Quote:
Q. Why are lighthouses painted differently? Do these designs represent something?
A. Lighthouses are painted different colors and designs to make them daymarks. So, if you were a Mariner out at sea during the day, you could look for the lighthouse. Let says for instance that you were off the coast of NC and you saw black and white swirling stripes down the lighthouse, you would then know that you were by Cape Hatteras. Or say you saw a lighthouse that had black and white diamond shapes on it....you would then know that you were farther south by Cape Lookout.
Q. If lighthouses are painted different to distinguish them during the day, how can you tell them apart in the dark?
A. Similar enough, each lighthouse also flashes a different sequence of light for the exact same reason. Cape Hatteras flashes a white light every 7.5 seconds. (The light actually rotates, but it gives the appearance of flashing from a distance.) Cape Lookout flashes a white light every 15 seconds. So, by scanning the horizon for the lighthouse, and then watching the light, you were able to figure out where on the seaboard you were.
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All you need to find is the local "plan" for the lighthouses circa 1938 or so... easy peasy
The US University of North Carolina apparently has someone interested in lighthouses around the world:
https://www.unc.edu/~rowlett/lighthouse/
perhaps someone there could direct you to historical data?