The shop is doing a 55 second series Chevy pickup right now and the owner had already bought a harness from Hot Rod Wires which do not have the routing printed on them. Not a problem with the guys as they have done enough re-wires to not need the labeling but I think most all have it anymore. The wires themselves are excellent with most being one gauge heavier than others and crimped/soldered ends. They do include a double spaced instruction page that is easy to read. A first timer might have to think about it for a while.
Putting an 18 circuit in a third car now (51 Merc) and highly recommend them for anyone familiar with wiring a car. As stated above he uses heavier gauge wire and while they aren’t stamped he groups them and labels them. Not sure how his pricing compares to others as I usually stick with suppliers I’ve had good experiences with.