Yale combination lock from 50´s

[svc]

Hello.
I got a Yale combination lock from 50's. My father bought this from USA when he was a sailor.
I hope If I could find some inside pictures about this model somewhere. I know the combination and wouldn't like to destroy a good lock.
There's also some stiffness with operation. I guess a dab of quality lock oil wouldn't do any harm unless there's any plastic parts inside?

[straightpick]

Check your email!

[svc]

Thank You! This helps.

[Jaakko]

As this is a forum for conversation, I would like to hear more and especially if there is disassembly pictures

[richardi]

I have exactly the same lock that I used to use on my locker at middle school in the 60's-70's. I have forgoten the combination. Can anyone help me unlock it?