I'm about to change the throttle position sensor on my 99 Ram 1500 with a 5.9L. The manual says to be sure the throttle is completely closed before tightening down the TPS mounting bolts. How can you tell which position is "closed"? Is there a way to visually determine this?

just look down the throttle bores, with the engine off, and also at idle, the throttle blades shoud be compleatly closed. also, don't forget to disconnect the negative batery cable when installing the new TPS to reset the computer.