TY very much Precision M6800. Your EFI folder not only allowed me to clean install Mojave on my M6800 (I've been trying, since before it's release to public), but also worked in my High Sierra & allowed me to upgrade to Mojave (always failed blackscreen prior). Both installations worked AOK with exception of getting the Audio to work, but I'm certain that other fixes will pop up eventually. I did try your Audio fix in the clean 1st (failed), then the upgrade afterwards, since it's Audio worked AOK prior to the upgrade, but still no device shows up.
View attachment 362509
Update: NVM. I got'er done on a clean install & using MultiBeast-High-Sierra-Edition-10.4.0 to install the Audio & Lilu.
Thanks again Precision M6800. Your success led me to mine. I'm very pleased with the faster startup than was in High Sierra. I prolly had it too garbaged up with unnecessary kexts.