c28 code, not revving past 9k from 3 to 6th gear not passing 120 mph.

You paid $225 too much.

15 are the throttle position sensors. The one to the left is the secondary, the one to the right is the primary.

Broken pins that need re-welded? Sounds like you've been watching the youtube videos of people who need their tools taken away.

With respect to the dash position (_C00). It should NEVER read low. Usually this is because someone improperly adjusted the TPS or they've turned the idle down from the spec. To adjust the TPS, the bike needs to be fully warmed up, and idling at the prescribed speed (1300-1400 rpm on a 600).