Looking for Accuphase P-300L Service Manual and schematic

Good day fellow DIY'ers,

I recently imported a Accuphase P-300L from Japan to join my small and humble Japanese vintage audio gear collection. I'm planning to use it as daily driver next to my Sony TA-N7B which I'm currently restoring from the ground up. Both connected to a restored C-222 pre-amp, but eventually to a C-200L pre-amp.

The P-300L is in excellent condition. Everything seems to work fine and it is completely stock and untouched. I already rewired the transformer wires to make it work on 240V. The option to do so on almost every Accuphase unit is fantastic. No more AC converters, at least not for this unit ;-)

As usual with Accuphase units from this era, they used top notch component. Lots of PP and even mica caps.

Although the unit works fine, I want to make it more future proof. Not a ground up restoration like I mostly do, but only replace parts which can cause trouble in the future.

Work to be done:
  • Replace all 'lytics.
  • Check and test the specs of the main filter capacitors. If not up to spec -> look for replacement (not easy with these dimensions.
  • Fresh thermal paste on the output transistors (or AAVID sil pads?).
  • Replace bias trimmers (known for taking out output transistors when they fail).
  • Check and test zener diodes, replace when out of spec.
  • Place fuses in the yellow wires from the transformer.
  • Replace all relays.
  • Replace speaker terminals on the with ones which accept banana plugs.
  • Clean all switches.
  • Maybe check the fusible resitors?
  • Adjust everything to the specs of the manufacturer.
To me it seems that the VU meters of the P-300L move to little to the right. At moderate listening levels they barely move. When I compare it to my Yamaha B-2 (comparable scale), of which the VU meters move a lot more at the same listening levels. I would love to adjust the VU meters to SM specs. There are 4 trimpots on the VU meter board for adjustment.

I looked on all known websites and forums for a Service Manual and a schematic, but no luck. I found one thread on DIY Audio where a fellow member claims that the problem of him searching for a P-300L SM / schematic is 'solved'. But not sure the member didn't need it anymore or he found it. Anyway, I do not have posted enough, so I can't send a PM to this specific member.

All help is welcome!

I will post some pictures of the Accuphase later on. I'm struggling with the new HEIC format of pictures that Apple uses in iCloud.