ammco 8000 brake arc

[Bruce]

Hey guys looking for a little help with this. I have a old ammco 8000 brake shoe arc machine. I want to use it on a project I'm working on.  My problem is I need to calibrate the machine. I just bought a reproduction ammco manual that covers the 8000 - 880 -and 800 models. The manual says to lock the adjustment pin in the 6'' shoe position and then drop the pin in the 3/16 hole (above the shoe scale). Problem is my machine has no hole in it. I've seen pictures of  other 8000 models that do not have the hole also. I was wondering if anyone has a manual specific to this model only or could talk me through this.