Benchmark dac and AntelopeAudio Isochrone OCX Digi

I think you mean Isochrone DA, the Benchmarks do not have word clock in. I would try am M2Tech HiFace first, eliminating the squeeze box.

I do mean the OCX. I believe it will clock on spidf in & out-read it on computeraudiophile. Not looking to chuck the squeezebox. I have a Benchmark and understand it does not have a clock input.

What is it you would hope to achieve by doing this? The Benchmark is largely jitter immune, reducing jitter to levels close to analyzer limits. See Stereophile's actual measurements, for what they are worth given the difficulty of measuring jitter.