Good news: there's no manual upgrade step. When a new member joins a VSF stack running a different version, it automatically downloads the primary and secondary images from the VSF master during boot and reboots a second time. That's documented behavior, so your 10.10.1070 box will pull 10.13.1110 from the master on its own. Budget roughly two boot cycles, call it 10 to 15 minutes in practice, there's no official figure.
Sequence: on the existing switch, vsf member 1, then link 1 with your chosen front-panel SFP port. On the new switch, same thing, vsf member 1 and its link port, then vsf renumber-to 2, which saves and reboots it as member 2. Cable the VSF ports (same speed both ends), power it up, and watch show vsf and show vsf topology until it shows in. Since you mentioned renumbering already, just confirm the link config went in before the renumber.
Two extras worth doing: connect the OOBM ports and configure vsf split-detect mgmt so a split brain doesn't take out the stack, and note mixing 6300F and 6300M is fine but the configured member type has to match the actual part number.
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Dustin Burns
@Worldcom Exchange, Inc.
If my post was useful accept solution and/or give kudos
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