How do I connect an outboard Headphone Preamp to my 976? I want to bypass the op-amp in the 976 and introduce a higher quality preamp since I listen to headphones a lot.

I want to be sure that the main speakers are "off" when I listen on headphones.
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Outlaw Model 976 AV Surround Processor
Outlaw Model 5000 5 Channel Amplifier
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