Hi everyone,
Thanks for the kind words!
I'll try and answer some of your questions!..
Have you sorted out any bugs, like hum, noise, etc?
No hum. Thick ground and star grounded to chassis at one point.
Noise is same as a neve really. Not noticible unless you really crank it, but then the neve is not one of the quietest pres around.
BTW David.... nice job son.
Cheers Peter. Should work nicely with one of your eqs!
There was a debate somewhere in one of the audio forums why a 1073 was not possible in a 500 series format. Said something about, not enough voltage to run it properly like a proper 1073 but you seem to have done it.
Whats the degree of difficulty on this build? Sourcing parts, soldering and construction?
Can you please put up some audio samples? I would love to hear this unit. 
Yes, the circuit uses a single 24V rail whereas the API lunchbox gives +-16V. So a DC-DC converter is used to convert from +-16V
to 24V. OR when groupdiy lunchbox is available, you can use the 24V pin. (no converter necessary)
I'd say it's a straight forward build. Of the 3 gain stages, 2 are the same in parts and layout, and are right next to each other,
so easy to stuff and visually check. Very little wiring (which I always consider to be the time killer.
Mouser/audio maintenance parts.
Sure, I can put some samples up too.
As far as sharing. I'm all for 'share the love'. I can order some more pcbs after xmas/new yr. I can order more metal work too I guess