I measured from the point where the shaft exited the housing, flush. Then to the outside

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I<~~~~~.731"~~~~~~>
The shell is the part the BB is house I assume. Ok I'll measure.
Since I had sucess pulling the cranks I went ahead and pulled another from a smaller bike that had Acera cranks with the same tooth count and installed them and adjusted the derailleurs so it would shift. Somewhat anyway. The angle of the chain looked very extreem while on the 42t front ring and the 11t rear chainring. It was very slow shifting too. The front shifted fine.