Looking for a schematic Diagram for a NPS 605W

[Deltatango]

Got a blown up NPS 605W power supply (60v and 5A) which I am struggling to fix, managed to repair most of it got the 60v working along with 5Amps but has a limit of about 70W.

Just need to understand the related circuitry to get that 300W output.

Has anyone got a circuit for it please, it has been around a long while so feel sure it must be...

Thank you...

David