Where to mount cpu

Wassup everybody? I just bought a 4th gen ls, and am installing the interior. My question is the brain is sitting on the passenger floor under the glovebox and i am not sure where the proper place is to mount it. Can i just use brackets to mount to plastic under dash? I would like to put everything where it belongs, but I don't want to be driving it around with the cpu sitting on my bare floor (carpet should arrive tomorrow) Any input would be greatly appreciated.