looking for schematic for Epiphone Zepher "Dreadnaught

[pula58]

looking for schematic for Epiphone Zepher "Dreadnaught" from 1950's

This thing is a mess...schematic would help.... if anyone has one.

Thanks !

Preamp is 2 6SJ7' pentodes, then phase inverter is a 6SN7, two 6L6 output stage, tube rectifier, and thwo other 6SN's for the tremelo circuit.

it has three inputs, equally weighted.

1st preamp tube:
* It looks like the suppressor grid is connected to a voltage below ground (-the resitive didier between -20V and ground is so old it turned to dust, so I don't know how low the suppressor grid should go- I have never seen it connected to anything lower than ground before).
* The grid is leaked through a 12Meg resistor to gnd
* The cathode is grounded.
* The screen is at 20V.

This weems weird to me, but then again, I have not worked with a lot of old pentode inout stages with grid leak bias.