I think what the OP could also do is watch this video https://www.youtube.com/watch?v=1VYhyppWTDc and after this another one https://www.youtube.com/watch?v=TQ34hed0qBw

Edit:
I was in the same doubt of the OP, I am 188cm tall (6,16ft) and after I saw that videos I was able to note that 58cm fits me better than 60cm. Also, the total TT was the same as the OP told in another post, 578mm for me, with a stem that can be 110mm to 120mm depending how much relaxed or aggressive position I want to ride.