I am using the stock wiring harness except that at the bulkhead, I had to bypass the blue wire around the bulkhead last year due to a burnt connector. Since the bypass, it ran fine all last year.
This came up on my last thread so I will throw it out there. I just installed a MSD ignition box and on the 12v switched feed to the MSD box, I connected three wires, the RUN blue wire (goes to the alternator/VR), the brown CRANK wire, and I also wired in the voltage guage that is showing a fluctuation of 13.5-14.5. These three wires are what is feeding the MSD 12v feed. I asked a MSD tech about wiring the voltage gauge in on the 12v supply and they said that it would be fine. I am not 100% sure on this as other board members have questioned it too.

Thank you.