Its well known that radio manufacturers in some cases will use whatever color wire they either have on hand or is cheapest at the time of purchase. So the hot wire could be blue, brown, red or any other color. This can change month to month or year to year sometimes. This would explain a difference in wire colors.I have gotten info before from Barkette's, and the tech was always right.
I don't know Nomad, yet.
Relax, welcome to the forum. These are good folks here who have lots of knowledge to share.