Perhaps I've mis-read something here Arvind - but you've posted some potentially contradictory info, which could well change the advice completely.
In post 1 you've said "I have 2 v6 boxes and 1 tivo boxes", you're now saying "I have two v6 boxes"
2 x V6 should be ok to migrate remotely, this should just be the software download.
If you have further additional boxes and/or any TiVo's, this will complicate matters. Any TiVo's will need swapping regardless and you'll likely lose the storage on these when they're swapped for a mini-box.
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