As far as wire colors being different. I have seen this several times on machines and my guess would be while building machines they ran out of certain wire color wire so that just used something different they had in stock. When you stop and think about it with a half of a mile of wire in every machine and all the different colors it is kind of surprising it didn't happen more.
One that I always think is funny is the harnesses on early SS machines that have 95% plastic wire and a couple cloth wires mixed in. You know they did that just to use up old wire!
Can you imagion how many rolls of wire a company had to have in stock to build harnesses for several thousand machines each year!