I found the easiest way is to wrestle it in two stages.
You start the match already damaged from the earlier encounter, so the first stage is you need to level the playing field - I find the best way to do this (assuming you're the babyface) is to do lots of top rope dives and planchas to give yourself lots of momentum. As soon as you max out, go for the finisher: not to get the pin, but to weaken OJ as much as possible. Even on Legend difficulty, it shouldn't be too hard to get finishers at a rapid rate, and with luck, you can get him to orange very quickly.
Once you've done that, leave the ring, get your stamina back up, then treat it as a new match, where you're both starting from the same level. Assuming you could beat him in a normal match anyway, there's then no reason you can't beat him again.
Also, it might just be me, but on the handful of times I've wrestled him, I've always found Orlando to be very easy to get pins on with normal moves, even when he's not in red. While his body has been on orange I've gotten wins with a german suplex, a powerbomb into the corner, and other powerful-but-not-finisher moves. Maybe that's just coincidence, but it might be worth trying some earlier-than-normal covers to see if it works for you.