727 will not kickdown

i sold a good cope built 727 with a rmvb and all the good parts inside.because im leaving this duster to my daughter,and wanted it to be an automatic so she would not have issues having to manually shift. new trans has all these shifting issues,makes me wish i would have just kept the crt trans.i thought if i got a automatic trans for her all would be fine.not so much.having second thoughts of getting rid of my cope trans.