Unfortunately all the products he used are illegal now and aren't sold
I'm doing a sub and two tempests piano black right now. I did a piano black Fusion 8 MTM last summer, it turned out quite well, EXCEPT the seams are visible. I blame the wood filler. I am using Bondo now, and I can tell it is much better.
You can look at my threads in my signature I have quite a bit of info in them on piano black, to put it short:
you need a PERFECTLY smooth box with ZERO seams. Bondo is great at this. Sand bondo with 80 grit then 220 before paint.
The urethane 2k primer I used is AWESOME it is way way better than zinsser bin that gets recommended a lot. You need a HVLP and compressor and spray mask etc. etc. though.
I'm using all car products bought from an auto paint store.
After paint and everything, to get the final "mirror" look you need to buff the paint with rubbing compound and polishing compound to get the shine. Piano black is not easy or quick, it takes many hours, probably 50+. Duratex takes like 3 hours maybe. Piano black looks amazing though