Backhoe Need to ID this unit, its on a 69 Ford 4500

[Ridn2]

I am looking to ID this to get some manuals and I can not find any Id tags on it, the only casting marks I have found are in photo attached.
Thanks

 

[herringchoker]

On a 4500, it's probably a model 755 backhoe with 15 ' digging depth.

http://www.jensales.com/Ford-755-Tractor-Service-Manual-FO-S-BKH-750_p_72072.html