I upgraded as far as i could take it without changing internal components.
Some fading on lettering .
The MKIII is a selectable OTL or transformer output amplifier that pairs nicely with high impedance phones and most low impedance through the transformer.
Installed is a NOS 1958 5751 Triple mica ,black plates,D getter sylvania/branded united electron ,bought new in box used for about 150 hours,amazing ,low distortion clear and powerfull,just in another league compared to all others 5751 i tried(with the exception of the telefunken nos)
Power tubes are a tested and matched pair of early 50's Phillips/Miniwatts,black plates,D getter. bought from Brent Jessie at Audiotubes,fantastic tubes .Over 250 just on the tubes alone.
Power cord is an Audioquest NRG-2 6 Feet.
Also included is the manual with schematics for future upgrades .
Thanks for looking.