Step 9

 Insert the eight PN2907 Transistors.  Spread the legs apart and insert it so that the flat side is facing down to give the appearance of a bell when looking at the top.  Put it in the board so that the distance from the bottom of the transistor to the board is about half the height of the transistor case.  You want them to be the same height as the PN2222 transistors which you put in last step.  Be careful not to push it all the way to the board as you might break the legs.  Turn the board over and tack solder one leg on each transistor, check to make sure that they all look straight and then solder the other legs and then trim