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Cool thanks. It looks like the person who previously used the cranks was running it on the inner ring. I might install the arms on the current bb and measure how far they need to come out to not hit the frame as well to be sure that a 4mm increase from what I have now. I might just end up giving up on them and say they aren't compatible with the hub spacing.
markxrat
Scilly.Suffolk
You need to find out what BB your cranks originally took and work back from there: try searching for the model number (on the back of the cranks "FC-*****").
With the correct BB, the inner ring will have a chainline of 41mm and the outer, 46mm.
Assuming you want to use the outer ring position the new BB needs to be 8mm shorter: 46mm - 42mm x 2 = 8mm).
Velobase can be handy for checking old BB requirements, but your cranks aren't listed. There are a couple of Exage variants though, which took 115mm and 113mm BB.
In which case you are looking for a BB around 107mm.
If your cranks still don't clear the chainstay, then you'll need to use the inner position and recalculate.