Thanks
@CaseySJ -I'll try it in a sec. The Z390 is the Designare (F9i, CFG-unlocked, CSM off, iGPU off, RX580, iMP config -the usual setup) with the i9 9900KS that you see on the left under my icon. That machine is flawless and is superior to any Mac I've ever owned. SIP is enabled on both boards.
The Z370 (F15a) is being remade as an OpenCore machine, so it was "flattened" first: Low-level reformat of all attached SSDs, CMOS reset and BIOS reflash to obliterate any traces of Clover and any underlying RC script stuff.
The two machines are essentially identical in components except one has GB-Z370-GA7, a i7 8700K, and a Titan Ridge Rev 1 AIC in slot 4 (RP21). Both the Z390 and the Z370 were created as clean Mojave installations with an OC Mojave installer USB. I'm hoping to have it setup as an OpenCore 0.6.4 machine. The USBInjectAll 0.7.6 is commented-out until I move to Big Sur or Catalina. I'm writing this message on the Z370 right before I try the EFI you shared. Thanks again.
Update:
@CaseySJ : The config file worked great! Thank you. The only pre-os boot message I see now is:
OCS: Failed to parse string field as value with type integer and <0> context <ScanPolicy