Ishmael, They are damn lucky that they are oil. Otherwise they'd be loaded down with coal. 1952-30=1922. Most low cost ships of that era were coal fired steam ships. Two boilers and one tripple expansion engine. The ship would be wired for 110Volts DC. (Just ask poor Moe.) The pannel would be open kife switches. I'm basing the Possum on a WWII Liberty ship called the O'Brian here in SF. The Liberty ship was based on an 1890 British design, so it is about the right era for our story...

-Fadac