Go to the Junkyard ending transloader. There are some pools of gook. Enable the "Invincibility" or "Never take damage" code. The car in the third pool sinks when you get on it. Once you get on it and it sinks, turn into a mouse. After the car comes back up, a picture of Bob appears along with some health bottles (not vials). Each one is worth five vials. Get the first two. Jump on Bob to get the last three.