dUbLEo ... make an image of my current installation and reinstall Solus to the same drive but using GPT format and then re-image from the backup I made ...
I've been waiting to see whether any of the technical gurus would weigh in about the idea of installing Solus as a fresh install and then overwriting the fresh install with an image of an older (but current) install. So far, no luck.
I think that there are advantages to rebuilding your system from the fresh install (that is, installing the apps/packages you use from the Software Center and copying your data from your backup), rather than trying to overwrite everything from the image.
If your current build is "many years" old, chances are that you've installed and uninstalled apps/packages over the years, and it is almost inevitable, no matter how careful you have been, that your current system has its share of cruft by now. Overwriting the fresh Solus installation with the old image will bring all the cruft into the new build.
I use disk imaging to replicate installations on several computers, and I do ground-up fresh installations as well. Although it is arguably less time consuming to image an old build than to build fresh, I suspect that a fresh build will be more satisfactory. Kind of like newly washed clothes.