Are you measuring your inseam with a book? Stand barefoot on the floor, back against the wall, with a book (also tight against the wall) firmly pulled up into your crotch! Then measure the top of the book.
I wear size 32 length trousers, but measure 33.5" using this method.
I am 6', down to 188#, from 212, and comfortably ride a 61. A 58 was suggested, but I feel more comfortable spread out a bit. The 58 just felt cramped.
Ride two bikes of the same model. Have them both set up identically, same tire pressure, everything. You will know instantly which one fits best.