George Wright Preamp Maintenence

I don’t keep a lot of gear long term. If I don’t listen to something on the regular I try to find it a home. That being said I have a soft spot for George Wright preamp and especially phono preamp. They are not new pieces and had started acting quirky. I went through and luped and cleaned all pots and switches. I found a crispy resistor in my AG Phono. It appears to be across pin two and five of the 6BM8. Does anyone have a schematic for the AG Phono or the AU-1500 and AU-15PU? Here is a collection of pics not seen often the internals of these pieces.