Cinelli Vigorelli sizing?

like i said i fitted the bike to my friend and the 58 fitted him perfectly

To the op, the actual top tube length on the 58 is 56.5 CC and the seat tube length is 54 CC.

i still don't see how your friends perfectly fitted bike is going to determine if the cinelli fits gogosama?

but it's the effective top tube length that matters.
because of variable angles of top and seat tube there is no direct relationship between actual top tube length between different makes of bikes but the effective TT is constant.
i dont see the actual tt measurement for the bowery on the giant website?
according to the specs the effective tt of the large is 58.5