I am 1.74 with 82cm inside leg measure
well you will see that the relationship between frame size and "bloke" size is not a "hard in stone one"
I can ride a 50cm (c/t) frame but is not going to be as confortable so I must use a shorter stem.
it also depends on the frame age as earlier on, top tubes could be significantly longer
and apparently "east coast" US frames tended to have shorter top tubes than west coast one
With suspended forks, top tube has tended to get shorter.
longer top tubes makes the bike a bit more stable at speed
shorter a bit more nimble
as a conclusion, top tube length is the most important one for the rider I think.
Stem length allows to adjust for confort.
Flat bar or rising bar will influence also ( more racy look and posture for flat - rising bar helps for when you get older so easier on the back and neck
if you are between 1.75 and 1.78 then the frame should be the right one
and you treated you well for a starter
one of the best 3 US framebuilder !
saw the auction but did not follow it. but was reasonnable ? compared to a brand new frame with same firm