I know this is not groundbreaking, but it was much easier than I thought and went without a hitch, so felt it was worth sharing. Late 2013 15"inch MBP running 10.12, with an internal Bootcamp partition running Windows 10 which I wanted to move onto a 256 GB Samsung T3 SSD external. 1. Starting point was applying this simple registry edit on my internal Bootcamp. I found out about this on the Winclone site. 2. Made Winclone image of the edited internal Bootcamp. 3. Formatted the Samsung T3 to MS-DOS (FAT) in Disk Utility, leaving it with GUID map. 4. Disabled SIP (essential before restore with Winclone) 5. Restored the Winclone image to the Samsung T3 6. Re-enabled SIP 7. Deleted the original internal Bootcamp partition with Boot Camp Assistant. 8. Booted to new Bootcamp with Startup disk SysPref pane. EDIT Only just noticed the other long thread on same subject...should have posted there.