I have an '05 and did not do the jumper mod. I went the Power Commander route.
For those that have done the Barbarian mod I'm happy it worked for you.
Something I did not like about the write-up was that the ECU has the male half of the connection and the wiring harness connector has the female half of the connection. The write-up says to use either a piece of wire or a resistor through the holes of the wiring harness connector. That would have two males touching each other (eeww!) and the potential for poor electrical contact.
This is on the '04 (and '05) instructions, the previous year bikes actually move over an existing female wire, so no issue.
Just some food for thought.
Len