seem 을 that 절로 바꾸기

It seems that he had been honest 라는 문장은
It seems to have had been honest 라고 고쳐쓰는것 맞는건가요??

제가 seem to를 that 절로 바꾸는걸 원칙적으로만 익혀서 그런데, 원리를 알려주시겠어요???