You could strip out the bottom bracket and take the frame to a lbs and have them face the bb down 2mm each side and you will be close to a 68mm bb length.
__________________
72 Geoffery Butler, 72 Gugificatizion Witcomb, 72 Raleigh Gran Sport SS, 74 Raleigh GrandPrix dingle speed, 74 Raleigh international, 81 Centurion Pro-Tour, 85 Gazelle Primeur, 29rBMX, Surley Steamroller 650b