How can I switch the names of my original C: drive ad its cloned copy?

You can't create a backup image on the same partition that you are imaging.

You can create a backup image on the same Hard Drive, but it must be saved to a different partition on that Hard Drive.
You could also save the backup image to a different Hard Drive, such as a USB external drive.

I do it both ways, i save backup images on multiple devices.

I played with cloning years ago, and it didn't work well for me, so i have no recent experience.

Your screen print (notes) in post #10 shows
- disk 0 is the Active/System partition, so that is where the boot-loader is used from to start Windows.
- disk 1 is the Boot partition, so that is where Windows is running from

You want the disk 0 [G] partition to be the Boot partition.
If you disconnect Disk 1 and a re-boot doesn't work, you probably only need to run Startup Repair to fix this.
Startup Repair

Well, I finally given up on fixing the previous mess, and just made a new clone with Macrium. And it worked perfectly! (Wel, at least so far.) Here's a screenshot:



Thanks for everyone's help, I'm incredibly grateful.