Yup, that's it! The power amp part of the schematic you linked to is exactly right. Only one difference: my amp does not have a 5 amp fuse at the output. That may be a wise upgrade. And nice to know what the output transistors are.It's a 'Park Marshall' from the '70's. The darlingtons are MJ3001 / MJ2501.
I will, thanks a million for your information!It's a nice vintage mixer, take good care of it.