Talk to a machine shop.If you don't like the answer get a second op ion. I always thought the old valve seat could be cut out and a hardened seat shrunk into the head. I had a chevy small block head repaired that way.
I really don't know what heads they installed on mine but assume 72 open chamber. Looking at the build invoice $140 for lead free valve seats , in 2008. Don't know why quench heads would be exempt from this repair. We are blessed with multiple quality machine shops in our area.
I have tried to attach a photo of seats for a Windsor Ford, only for an example.
I was hoping someone would chime in with expert Cleveland advice , I learn something new here every day.
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