Thank you for this valuable advice, ticklemefeet. I really hope this helps someone else who isn't experienced with this. Here's what was ultimately accomplished. Thank goodness it resulted in a viable image and backup system. I had serious doubts based on the USB failure which I'll recycle as a data storage unit and reinstall Windows PE on a smaller USB.
1. Disabled startup of the Macrium UI Watcher. It dragged startup by about 2 seconds.
2. Put the system image on another Western Digital HDD--I have three but only one enclosure
3. Left the Windows PE on the Pny USB
I just verified this clumsy setup, it's perfect. I'm going to leave it like that because the image is good and my computer boots straight from the rescue USB (it has four USB ports). I started over with trying to install PE and then image. Macrium refuses to put the PE and the image on the same stick. I tried and tried, using DiskPart multiple times to clean, format and re-partition the stupid thing. There was 57 GB free, I formatted it but during the imaging process, it would fail, stating not enough space in the destination folder (E:\). Then, clean, reformat, rinse and repeat. As long as the image is verified and accessible, that's the desired but less-than-ideal outcome.
Again, thank you for your help, ticklemefeet, it's really appreciated. :emoji_ok_hand:
Edit: added the snips to show the two different drives.
Edit2: oops, didn't add another partition to the USB for the image to reside in. OK. Live 'n' learn.
Still aggravated so I'm leaving it as-is. It works!