Old Worthington Air compressor setup... hoping to avoid any dangerous issues.

[Whimsydome]

Hello everyone I'm new to the forum and was very impressed with a lot of the other threads I've read on here. I have looked at some other threads that are similar to this one I'm starting but they aren't quite the same. I have what I believe to be a unique set up ( wish it was standard). It's an old Worthington air compressor hooked up to what I believe is the original tank and I haven't gotten around to looking in the tank but I will before I start it up. I also need to check the pressure relief valves to make sure they are operating and such. It has a 18hp Briggs and Stratton engine on it.
My questions/ concerns are this

1: Does the plumbing look corrects assuming it all works as intended?
2: is how the engine is connected to the compressor correct?
3: what kind of cfm can I expect from this thing?
4: What else should I add to this set up for added safety and better operation?

I want to add an air line cleaner even though it has some very old style ones on it.
I'm concerned that its not all hooked up correctly or something as it is home made( I think)

The picture of the tag states that it is
Serial #- 223U 169
Size- 4 7/8 x 2 7/8x 2 1/8
Model- 7 1/2- TBC
I plan on calling worthington in the hopes they can give me more details on the specifics of the pump so i know how to run the engine.