@SinclairSpeccy After been reading through the paper from 2020 on the boot sectors in use by the #ElkCloner, it is clear that to get it working, the disk should be a slave and not a master disk. There are three areas of the boot that needs to be adjusted, track 0, track 1 and track 2. On track 0, the area $0A00 ... $0B00 should contain the loader part of the Elk Cloner. On track 1, the jump located at $1080 should be modified to jump to the Elk Cloner code instead of the regular DOS part. On track 2 the Elk Loader should be installed from $2300 ... $2400 (it occupies only two sectors and even though there is more empty space after the occupied part, it overwrites a few bytes at the beginning of $2300 which are set, but obviously not used, $00 and $ff bytes). I have been sitting looking with hexedit on original disk images from DOS 3.3 analyzing the structure and what happens to it with different alterations using image tools. The AppleCommander seems to refuse to overwrite the boot sector of the image it creates, so it is not that straight forward to get it on e.g. location $2300 with e.g. the small utility 'ac' from the #AppleCommander package.