It depends on how you see the things you're describing in your mind.
There are subtle differences that variations in the punctuation can convey - for instance:
in her middle-to-upper-60s
treats the whole phrase as a compound noun.
It's like saying 'She was in her kitchen'.
in her middle- to upper-60s
puts the focus on both ends of the stated range.
in her middle-to-upper 60s
treats 'middle-to-upper' as a compound adjective.
It's like saying 'She was in her warm kitchen'.
in her middle to upper 60s
has the potential to confuse the reader, who might first read 'she was in her middle' as a complete phrase before getting the intended sense.
So, yes, in short, your examples are correct grammatically - however, do they accurately convey your meaning? Only you can say.