Justice Sandra Day O'Connor (ret.) served our country with distinction and honor during her time on the bench. She carefully crafted her decisions on a case-by-case basis and refused to be doctrinaire. She was a centrist. Balance is needed on the Supreme Court if justice is to be served.
In retirement and even prior she staunchly defended the independence of the judiciary. She criticized Citizens United.
She was appointed by President Reagan and as such she ought to be immunized against those who would deny you your Constitutional duty to replace Justice Scalia.
We do not know if she would accept the appointment and if she did it would be understood that it would not be open-ended but rather she would determine her departure date once again.