That should work for the spoiler, and is a common solution. You should get rid of the cross bracket that holds the motor. I can't recall for sure if there are feet that help bolt the tubes to the floor on each side for stability. Maybe that's what's bolted to your cross bracket at the bottom left corner of your photo -- remove it from the bracket and put it back on the tube, bolted to the floor.
I ended up using the aluminum bracket, without motor, to stabilize the spoiler. Also, here's the $9 tow hook (strap) solution. It's rated at 10,000 lbs or so.
Rear bumper screen done. I cut the hole a bit smaller than usual so I could offset the screen inward and keep the rivets off the front face of the bumper cover.