help finding a shematic for this push pull 6P3S (6L6GC) Russian "hifi" amplifier

[ELS122]

I bought this amp and converter it to a JCM800 style amp.

it used a 5Z4S rectifier, 2x 6P3S power tubes, 6N1P PI tube, 2x 6N2P pre-amp tubes.
the power supply was: rectifier - 4uF cap - choke - 20uF cap (connected to power amp), - 20k resistor - 10k
the screens were connected directly to the center tap of the output transformer, it was cathode biased. the center tap of the output transformer was connected AFTER the choke.
nothing connected before the choke.
it had 2 mic inputs, each has volume pots, and an aux input, it had some tap on the output transformer for an NFBL I supose, it wasn't connected to the output.

the oldest tube is dated 1963, it's one of the power tubes. rectifier, one power tube, one of the preamp tubes. are dated 1972.
one preamp tube dated, 1971, and the last one dated 1967.
one tube shield dated 1957, another 1970, and the last one seems to be dated 1955 (not sure of that last one).
oldest pot is dated 1968, newest - 1978.
transformers seem to be made by some "KD" company, in the logo there's a Russian "K" and "D"
the power transformer seems to have a center taped 13.6V heater winding (or 2 6.3V that are connected together in one point)

and yeah I probably should've found the schematic (if there is one) before I re-did the entire circuit.

the middle is the choke, the smaller one on the end is the output transformer, and the biggest one is the power transformer.
(also yes I know, the layout of the transformers is bad, but It'll have to wait for a new chasis probably anyway.