Hi Dan….I just did something similar. First off, good plan wrt your vaults and having time machine. That being said, the only gotcha I hit was making sure the *project* was highlighted when relocating the masters. At first, I was doing a select all and relocating. But if I forgot to open all stacks, or clear filters, I’d miss some files. I’ve got some menu screen caps on my blog that give you the visual clue you’ve got it right.

I’d also recommend having a smart album that looks for any photos that have the file status as “managed”. Once you think you’re done, check the smart album - it should be empty.

Good luck,
-scott