Hasn't been done in a while. I watched some bouts by Olivares lately as I have always liked him. He seemed surprisingly slow, much slower than Morales. However, his body punching is wicked and very accurate and his punching power is devastating, plus he was the better all around fighter. Difficult pick
I agree with you that Olivares was the better overall fighter, and I'd favor him by decision. Morales' weakness, outside of his crappy D, was that he didn't have all time great stamina. I think Olivares takes advantage of that.