Try using a stethoscope. It is an older safe, so it is possible that if you hold a stethoscope to the lock while turning clockwise, you might hear a click. That is your first number. Turning counter-clockwise now, wait for another click, your second number. Go clockwise again for your third number/click, then try the handle while the dial is still on the third number.
A Very interesting facility you have there, do you have video tour of i the bunker??? Also I would love to give the safe a try : 36-24-36
Try using a stethoscope. It is an older safe, so it is possible that if you hold a stethoscope to the lock while turning clockwise, you might hear a click. That is your first number. Turning counter-clockwise now, wait for another click, your second number. Go clockwise again for your third number/click, then try the handle while the dial is still on the third number.
Try combo 15 45 75
I guess the code is: 34 56 97