Yeah, I just wasn't gonna mess with the CPU until it was last or near to last on the list, despite having been working atop the CPU heat sink earlier. It's just how I roll. Anyways, think of all the fun I would have missed if I went straight for the CPU!
I'm grateful to everybody here who pitched in with excellent ideas! Thank you so much for your help. This is an awesome forum!
Now that the d8b #2 seems to be booting reliably I'm going to try to get this thread back on topic!
Thanks all!