It is pretty much straight up. Begin from the front end and finish at bulkhead plug side. Even I never have used the non stick tape ( unavailable down here when I made mines ) I used the self bonding 3M tape. I even used a cord at some places like factory did, for example where some wires are leaving the tape allong the run.
It must be in one trace without cut the tape. If the harness get a Y to run in two diff directions, the tape must be unrolled straight from the splice, parallel to the wires up to reach the end and begin the job like you were making on the other section of harness, wrapping the same tape you run straight untill reach once again the splitt of the harness, and once the splice is reached again, just continue straight to the bulkhead side. Dunno if you got it.
I bought 1 or 2 rolls of the original non sticking tape at Carlisle 2008, but since I thought it was to be not enough ( should bought couple more ) to make the full car, decided to use the 3M one what it was available down here at shops, to make all the car equal.
My car got several parts spliced and covered with regular sticking tape. WHAT A MESS! I had to clean all wires with kerosene to remove the glue, then clean the kerosene with water and soap.