Newbie - communicating with old OSAI Series 10 controller units

Hello,

I've got a CNC machine running with an OSAI series 10 controller and I'm trying to get it to talk to a modern computer. Thing is, it's really stripped down and I'm not sure what's really left. I've been looking at the connection manuals and install guides (see http://manuals.cmsna.com/Support/Man...n%20Manual.pdf) but I'm not too sure how to relate that to a modern computer. I'm thinking my best guess would be the area labeled "Ethernet" in the one picture - only thing is, it's blocked out and I don't know if the original port is still there.

I figure I also might be able to use the "fake keyboard" approach - somehow connect to the keyboard port, then set up the computer as a keyboard (so to the device, it looks like it's typing out the G-code I need). That seems a bit complicated.

Here are my leads in pictures:
The port labeled "Com 2" in the first photo
The Ethernet port that's blocked out
The Keyboard port
The 25-pin port

Setup: The photo with the keyboard ports is behind the operator panel. It's connected to a big power cabinet that houses the controller unit. I wasn't able to track the 25-pin port to anything though.

Guidance: I need some help explaining what's going on here, what that Com 2 port might possibly do, whether you think it's likely that there's an actual Ethernet port underneath that blocking pin, etc.

Thanks,
John