REL Stentor III maintenance advice

[Michel8]

I need to replace the electrolytic capacitors in a REL Stentor III subwoofer (over 20 years old). All electrolytic capacitors, except two, are Rubycon YK.

I would like to improve the quality of the capacitors according to their role (signal coupling, power supply decoupling, power supply filtering).
REL does not provide a circuit diagram.

Can someone tell me the capacitors according to the sections of the amp from photos?

Thanks