Let's check what you've actually done here - bearing this picture of the boxes in mind.
V6 boxes can be converted into 360-master boxes (with hard drives), TiVo boxes will be swapped out for mini-boxes (without hard drives). When you say a TiVo was reprogrammed, I'll assume you mean a V6.
You can have upto 2 additional minis (or converted V6) per master. So 3 x 360 in total.
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