Wiring help and questions

In a week, I'll be making my electronics box and setting up the new machine!
1)Does anyone know where to wire the PWM and Spin Ena pins on a HuanYang VFD? What is the voltage on the PWM anyways? 5V?

1. I'd like 2 types of coolant on my relay, one is a vacuum (simply switches a power bar from NO to closed) and the other will be a compressor line for milling metals. This may be easier to just do manually, honestly. just asking.
   
   
2. Can I have the other relay control the stepper motors PSU? It'd be cool to have the whole box basically shut itself off via the arduino. Any pin option for that? If not, I'll just use a on/off toggle.
   

4)How does the feed hold pin work? I'd like to add my E-stop button, but without just losing power to the drives and my work position. The switch has one NO and one NC circuit, so if there was some way I can have it Feed hold when I engage the switch, then reset when I pop the switch out? Is that possible or will it just constantly reset itself as long as the circuit is complete.

Thanks!

Here is my current wiring set up: Imgur: The most awesome images on the Internet


please comment here so everything is in one spot
Pins options + Spindle Wiring · Issue #244 · gnea/grbl · GitHub

 

Nope. Says exactly that it doesn't cover the PWM

 

Looks like a dead group

I got most of it sorted out now anyways. Just need to sort out my power switches

 

Took some help and googling the right terms. Reading the manual helped. Ill post it all when the machine is done or someone asks.