Instructions
Play the game through World 1-4. The factory is at the end of World 1-4. Once in World 1-4, press "L" to become Phineas. You will need to be him for most of the level.
Walk towards the toolbox and press "Y" to open it up. It will be a radar. In the bottom screen, drag the radar into an open slot using the stylus pen. The radar is now equipped.
Walk towards the dot on the radar. The dot is the security guard. Walk up to him and listen to him. Climb the ladder behind the guard.
Walk towards the conveyor belt and jump onto it by pressing "A." Once you are at the end of the conveyor belt, walk to the red toolbox and press "Y" to open it. Go up the ladder near the toolbox.
Press "Y" on the toolbox at the top of the ladder.
Go west by using the radar as guidance. Go on the conveyor belt. Go to the pile of scraps at the end of the conveyor belt. Press "Y" at the pile to obtain the paint. Go west until you see the slingshot. Jump onto the slingshot to shoot you across the building. Press "Y" on the
Jump onto the slingshot to go back across the factory. Go east and find the broken control panel. Press "L" to change to Ferb, push the side of the panel away from the wall and go through the door at the end of the now-visible conveyor belt to leave the level and access the second roller coaster.
toolbox.