Help me identify this Yale forklift

I aquired this older, manual transmission Yale, 4 wheel, 2 stage forklift.
Guy that sold it to me didn't have any information about it's model, age, capacity, etc.
Obviously there is no plate, or I haven't found it, yet.

I'm asking the experts here to help me identify the model or give me a clue of where on the unit I might be able to locate model/serial/vin number.

Here is the link to pictures: https://goo.gl/photos/8QBoaAu8tUByo6F26

Thanks in advance for any information.

Few more pics

Here are few more pics:

In many cases, a Yale forklift’s serial number can be found in its electronic system or physically stamped somewhere on its frame.

http://store.intellaliftparts.com/blog/yale-forklift-serial-number/ Here is a list of many different models of Yale forklifts and where their serial numbers can be found, sorted into categories of walkies (pedestrian jacks) and riders. Some also list where their nameplates can be found.