PROPORTIONING VALVE LEAK

Hi Folks

Just the facts mam.......1971 demon with power Kelsey Hayes disc brakes and a Weatherhead proportioning valve.

I rebuilt the valve using the Muscle Car research LLC kit. With the engine out, I have been struggling with the sealing ring on the top fitting. I have tried several washers, tried annealing it, tried various torquing.......I thought it was solved on my last go around, so I installed the engine, and front suspension and now the F'n thing is still leaking. All of the flared fittings are dry as a bone. I really don't relish removing all of the freshly bent lines and swapping out the complete valve with the limited work space now.........Any suggestions?

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