Madelectrical guage bypass?

So I finally got off my *** and am doing the guage bypass http://www.madelectrical.com/electricaltech/amp-gauges.shtml

Im wonderring if I really have to connect the other end of the black wire that passes through the bulkhead connector Or if I can just make it like I have in the pic. (in blue)?
If the red wire goes from the starter relay and it feeds the black from the guage it's still getting power to everything right?