An 60k is easily an entry level salary. And 300k is easily a principal engineer's salary. Put the two under the same job title and then you can say to the jury, "it's not just credible that this salary range could exist, this range actually already exist right now."
They do at my company. Everyone is just "Software Developer". I don't see anything wrong with it, I find that titles are largely meaningless anyways. At some companies "principal engineer" is handed out after 3-4 years of experience, and at others principal engineer is the highest title with only 1-2% of devs holding it.
