Hi Mike,
In virt A you see my thoughts, which are:
- create a new top (yellow arrow)
- cut of old top (red line)
- pull up the first branch on the left, to create the caracter branch (brown arrow)
- make the second branch on the left, you back branch.
In virt B I tried to show it, I'm not so good as other in virts though, sorry
cheers Wessel