It is hard to say exactly how much of the black wire insulation was cut off of the 7-Way Round RV Style Trailer Connector # A7WCB, but after watching the video and having done this myself before, it looks like Rick cut off about 2 inches of the black portion and then about 3/8 of an inch of insulation per wire.
There is an industry standard for how 7-ways should be wired. If you check out the picture I attached you will see how they are typically wired. By function is how the connector... view full answer...