OK, I lied. This isn't July 30th..................
A home user could afford a little down time if the Windows 10 conversion and the cutover of apps, peripherals, etc. did not go to schedule. Since your "friend" (you
sly devil you) relies on her computer as a professional, I would want to be extremely conservative with my approach.
In the IT profession you learn that when something breaks the last change that was made is generally the first place to look for the fault. The nearly four hour outage suffered by the New York Stock Exchange earlier this month was blamed on software updates (NO, not Windows 10 !). That's why configuration management/change control is religion in many IT shops.
So, I'd preserve her Windows 7 configuration unchanged, and create a bootable Windows 10 install on the SSD.
Of course, if the friend is a real hottie, I might change my mind and HOPE that the fix will cause me to have to spend long, looooonnnnngggggg hours at her place......
.....Of course all my friends are pot-bellied middle aged bums who may not have any cold beer in the house when I come over to fix their computer problems. Sigh.....
....like I always say, if I was interested in sex I would
NEVER have gotten married...........
.......If I've offended you in any way, I apologize........