Keep in mind Surly LHT's are meant to be ridden on a larger size as it is a touring bike, not a race bike. A cross check of course, is slightly different however we size people for a Cross Check the same as we do for an LHT, either way the 42 cm is going to be to small for you. I am 5'5" my PBH is 80cm and I fit a 54 cm LHT (I can do a 52 cm but not a 42cm) To read more about sizing here is the bike hermit's post on measuring your PBH
Sky King
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Gilles Berthoud "Bernard"
Surly ECR "Eazi"
Empowering the Bicycle Traveler
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