Now that you have Clover installed and NvidiaWeb Drivers just download Clover Configurator Vibrant Edition (google it, if you haven't done it yet).
Open Clover Configurator and mount EFI partition and open it, inside goto EFI/CLOVER, there you have config.plist, replace with this. Now restart and it should work.
NOTE: Since you installed SierrAMDv4 and has you already know the script/path is wrong AND the kernel is mostly for Ryzen processors, Iadvise you to replace the kernel with the one from the Downloads section.
NVIDIA GTX 980
AMD FX 8350