Fixed this amp a while back and been running it day to day ever since. So far everything works and seems to be stable, I finally get to enjoy the music coming out of it 🙂
It's definitely quite a thing building and troubleshooting it in the past 8 months or so, major lesson learned is that I could've gotten a scope on day 1 if I could turn back time.
Many thanks to Kevin for providing such a design - the major heavy lifting of bringing back a great amp. Thanks to GeorgeP for supplying the hardware with all the building advices, or I would never have considered building one.
And a special thank to Simmconn, who spent a lot of extra time not only helped me with diagnosing the issues, but also taught me a lot of the nuts and bolts about proper troubleshooting practices in general as well as demystifying the T2 circuit to me through patiently explaining.
Of course there are a few more to mention, thanks to the folks out here who kindly helped me. It takes 10+ headcase veterans to help a newbie like me building a working T2 😄