Thanks for the great guide! I was able to successfully install 10.12.6 on my HP z620 after I tried to follow the guide to the details.
Dual E5-2643v1 >>> single E5-2667v2
Clover configurator classic edition v126.96.36.199
Kext Wizard and/or KextBea.....
Long story, first, I got the z620 with dual E5-2643v1 and decided to install 10.12.6 on it and I was able to make it mostly working by following your guide. Except only two out of the five USB2.0 were working after part VI of installation (fixing DSDT). After some attempts, I fixed this issue by installing RehabMan’s USBInjectAll kext (v2017-0724) into /library/extensions folder (5/5 USB2.0 working correctly). Also, I used VoodooHDA_v2.8.7 for the audio since the fix for 10.11 did not seem to work for 10.12.6. I believed I also got PM to work for E5-2643v1 using fakeSMC from multibea…….
At the moment, I got an E5-2667v2 and decided to move onto this CPU. However, I could not boot into the 10.12.6 because I got kernel panics (should have 16 threads but only found 17 for die 0) every time and none of the boot flags helped in this situation. BIG THANKS to @hugodlc!! I was able to solve my problem after asked him and carefully read his replies to this thread. Since we are using the same CPU (his is dual E5-2667v2 z820 and mine is single E5-2667v2 z620), I carefully compared his DSDT and SSDT to mine and make modifications on mine. Eventually, I was able to boot into the system and re-install 10.12.6 last night. So far, system seems pretty stable and everything seems to work fine (except USB3.0).
Thanks again to everyone who makes this possible!