Some sort of success has been achieved!
Using ShadowM's D64 images, I put them on a bunch of diskette sides and my SX-64 booted GEOS 2.0
It was a bit of a pain at first because ShadowM's diskfile comes configured for Mouse and I don't have a mouse. Some dabbling in WinVICE and I had made the necessary modifications to the disk (attached here).
What I did in the end is format a bunch of disks in 1541 single sided (flippy disk) mode and copy the stuff over from my 1571 double sided disk, read through my 1571 drive. It all worked fine and now my geoPaint Workdisk is backed up onto a fresh new diskette! Next step will be to put all that into a D64 for posterity.
Then it wil be the turn of the geoWrite disk
I am happy to confirm GEOS 2.0 files are compatible in both 64 and 128 versions, something I was not completely sure of.
Thanks a lot to everyone that helped. I still wonder if there's any tools for better use of Easy1541 on the Amiga. The D64 writing utility doesn't work on unformatted disk and I couldn't find any utilities coming with Easy1541 to format a CBM disk.