How did you get on with this project. I'd be interested in your ATK Preamp if you fancy flogging it?
I have two Japanese ATK's from the 90's (300 and 310)
One preamp has dead pots and I'm looking for replacements. The ATK pots are strangely long and the pins are mounted the wrong way.
I was also looking at the John East Preamp and original Ibanez parts are getting harder to find