Good match-up. It would be similar to pryor-arguello in that pryor would be facing a very patient boxer who would look for openings and counterpunch. Ortiz lacked arguellos power, however, and wasn't the most mobile of boxers. Would have early success, probably scoring a knockdown but would eventually be overwhelmed by pryor, who panama lewis would have pumped up by illegal substances and giving him an unfair advavtange like like had against arguello. This would cause pryor to be able to absorb punches that would ordinarily hurt him and give him almost endless stamina, which is what deprived arguello of a 4th tiltle (imo).
Ortiz was bigger, stronger, and better suited to 140 than Arguello, who was also past his prime by the time he took on Pryor. Not to mention he was much better suited to dealing with Pryor's onslaught as his strength and in-fighting skills were superb.
This isn`t an easy fight to call, but I`ll go with Pryor in the upset here. Aaron could box beautifully when he set his mind to it, and my gut tells me that he would have mixed a bit of boxing along with some his wild unorthodox come at you from all angles attack to befuddle Ortiz en route to a close but clear decision. In a rematch though I would probably favour Ortiz to make the necessary adjustments and win a decision, but even then I wouldn`t say its a sure thing, a motivated Pryor is a formidable opponent for just about anyone at or near his fighting weight and maybe he would beat Ortiz yet again, can`t count him out thats for sure.