How do you mount your MGM??

Could you tell me how do you install your MGM controler in your truck?
Can i put the heatsink directly on the chassis or should isolated it from the aluminium chassis?
I can see that they have 4 littles thread holes in the heatsink, can i use it to secure the controler to a an aluminium braket??

Or you just sit it flat on the chassis or a braket and use zip-ties to secure it?

Thank you!