This 1950 diagram shows 16g. Should be the same for your '54. The color of the wire may be different.
http://chevy.oldcarmanualproject.com/electrical/wiring/pdf/50truck.pdf


- Lonnie
My '54 3104
Photos that I have shared on Stovebolt via PhotoBucket are no longer available. Please contact me if you want a photo from an old post.
lonniecook [at] aol [dot] com. I sold my '54 3104 12/12/2017, but I still visit Stovebolt.

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