I would snug it up till it touches the frame and go from there. Prolly wanna make sure your motor mounts are in good shape.
Its gotta be a way better alternative to the alt bracket torque strap.
My guess is it wouldn't be very effective if your using poly motor mounts
I had a buddy order one once. I went to put it on, but due to his body bushings being a little wore, I would've had to hammer the body sheet metal and that big seam right there to install it. I didn't want to do that to a nice low mile car, so I talked him into replacing the body bushings first and going from there.