I want to thank everyone for their great help!
There are actually two lines on the compressor that I can't figure out.
1: The line on the very top
2: The line that goes on the side.
Judging from Frank's post, 2: should be the oil feed.
Where do the lines connect from?
I've included two pictures. The governor is remotely mounted and it is very hard to see. I will take pictures of it and update.
Thanks for your great help! I really appreciate it.
Also the bus is a FE with a Cummins 5.9L.
There aren't many TC2000 if any at all in my area. Most bus lines use smaller buses.