Many bb spindles are assymetrical, that is the drive side projects father from the shell face than the non-drive side to allow more room for the spider and chainrings.
You need three measurements from your old spindle; 1)the over all length, end-to-end, 2) the distance from the drive side bearing track to the drive side end of the spindle and 3) from the non-drive side bearing track to the non-drive side end of the spindle. If 2) and 3) are the same, the spindle is symetrical, if they are different, it is not.