The tuner is attached for the download procedure, but is then removed. Contrary to the PC, no hardware stays with the bike. The connector is where you say, behind the right side air cover. The tuner modifies the bike's computer at the source; the PC supplements the bike's computer. The tuner has lots more variables to adjust than the PC does, so a good programmer can do a much better job of dialing in the motor.
Diljera