This "like a thousand years" doesn't mean "equal to a thousand years". It is a simile, a literary device, where you compare something to something else, by using word "like". It is never meant to be literal. Simile is similar to a metaphor, where the comparisons of something to something completely different, is only symbolic or metaphoric.
No I am not taking it literal. "One day with the Lord is like a thousand years with man" is just way of conveying that the Lord operates outside of time. It is not meant to be taken liberally. Which is why I said that there is no way to determine how much time exactly Adam and Eve spent inside of Eden. Could have been 1,000 years of mans time, or 10,000, or 300,000. I cant give an exact number because there is not enough info to calculate an exact number. All I can say with confidence is while Adam and Eve was in Eden time moved considerable quicker outside of Eden. Theory of Relativity gives us some insight as to how this can be. Perhaps God has an extreme gravitational field around Him or something else that would cause time to slow in his vicinity.