Ok, so I just got my NOS roto crank in the mail and the square hole in it is ISO. I measured it to be about 13.6 or 13.7mm. compared to a shimano JIS square which I measured at about 14mm. From what I understand If I put an ISO crank on a JIS BB it will go on, but be off of the axle by 4.5mm. getting to my question, I pretty much have to get a JIS BB because its the best price on french threaded I can find (its the velo orange french threaded BB) should I calculate plus 4.5 when considering my axle length? for example, If the crank will hang off 4.5mm and I get a 107mm BB axle does that mean that after mounting the crank it will be set at about 111.5mm?