Process in opening an old York safe

I have an old York safe that I have the numbers to but dont know the process of how to open it ( left right how many times to pass it etc.) It has two locks top and bottom. I need to get in the bottom safe. On the label I believe that the serial number is Y24679. the SPEC number is B1. S.M.N.A Group is 4. On the top I see numbers sketched in which may possibly be the serial number, it reads M1396. Any help would be appreciated. Email me at bjburton79@yahoo.com for any extra details. Thank you.