It's the same as any other mosfet, I have a better picture for the wiring tho.
Cut on the red crosses. The 2 green wires become the trigger. You can solder the perun wires directly to them (polarity doesn't matter)
The 2 blue wires are the motor wires, Polarity is important so pay attention.
If you want sexy wires then you need to add in a set of deans between the mosfet and motor. You just about have space with a gate nanohard so the perun should work as well. The micro connector is also nice but not essential.
When your done if you get the wires all nice and reasonably tidy you should be able to fit it all in front of the backplate.
This is it done with an Xcoretech XET304u but I've done a gate nanohard in exactly the same way.
Because the perun AB++ is a single wire trigger you will have to tap into the red main wire as well. If you are going with a deans split then you can solder that wire to the mosfet side of the deans (not the motor side). You want it on the mosfet side so when you work on the gearbox you can completely remove the motor and move it out of the way. Give me 10 mins I'll edit an image of the deans location.
Here you go.
Purple crosses are where the deans goes for the motor connections - Cut those wires where you need them
the image is not to scale.
The green are the trigger wires. You have to add a new wire to the back of the motor connection deans for the trigger. Again not to scale so pick a sensible length for those wires!