Hello BadToad2016,
I went ahead and did a fresh install with a Win10 v1809 installation media. It went smoothly. I think it may be the disk driver. The update broke my RAID-1 (mirror) and displayed the message inaccessible boot device.
I have a similar issue updating Win10 v1809 from v1803 on another PC. The system has a SATA/SSD drive. As soon as I have time, I will put in an HDD and test.
With Win10 hung after the update, there was no opportunity to debug. Since it hung before accessing the drive, I suspected that it's the driver. Hopefully, this is enough for MS to bug out the issue. There are more people posting on this issue elsewhere on the net.
tdn4it