slate_leeper aka Dan Z wrote:

My Win-7 was purchased as an OEM installation CD from Amazon. I bought
it legally, and have the CD. I installed it on my new (then) ASUS and
it works just fine.

Win-10 on my new Dell is a disaster. I would love to install my
much-customized Win-7 on it via restoring a disk image from the ASUS.
However I am sure that will result in an "unlicensed" installation.

Is there any way I can license it? I would be happy to pay MS for
another license for the Dell.

Lots of online articles about changing the license key for an existing
installation. You would copy your backup image to the other computer
and then change its license key to a legitimately purchased one.

https://www.lifewire.com/how-do-i-ch...ct-key-2624930

Just in case, make sure you save a backup image of your Windows 10 setup
should you decide to move back to it.