Stonyb3165,
I am not familiar with the Oppo connections and formats, so I'll be of no use there. As Soix mentioned I use a Denafrips Iris DDC ($550) to convert USB from my streamer to I2S to the Pontus II DAC.....the Iris only accepts USB. Using I2S is a game changer in SQ, worth every penny. Does the Oppo output USB? Is it even worth it going this route with a decade old player?
The only CD transports that I know with I2S outputs are the Pro-Ject CD box RS2T, Nuprime (CDT 8 Pro, CDT 9, CDT 10), and the Jay's Audio units. I've tested the CDT2 MKIII connected I2S to the Pontus, and it was glorious......eventually what I'll end up with. I'd look at this as an option knowing you're up to date with current technology.