keep in mind lots of BB are asymmetric, and the size depends a lot more on the cranks/chainring position. probably be better just to note they use a chainline other than 42mm and let people figure it out and/or point them to a detailed explanation of chainlines like SB. example

this is all true. the whole conversion and road cranks may be an issue here. i'll see if i can't clear it up and keep it simple