They may try to provide 100% correct wiring. But if they provide cloth/braided-covered wiring harnesses for a 1954 Chevrolet truck, they are wrong.
However, I think at least one of my 54 trucks had cloth-covered wire on dome light housing from switch to bulb. I do not recall finding any other cloth covered wires. I'll try to remember to look at a few of my 54 dome light fittings tomorrow.
By the way, is your dome light lens plastic or glass?