Darn Olds guys keep cluttering up the place!!! (That is a welcome aboard from another Olds guy!)
As for tying cars down, I look at how the haulers carrying the cars and trucks out of the assembly plant do it. 98% attach to the frame and pull straight down. Some of the new transport are using the wheel nets.
I myself use the t-hooks and the frame slots and cross the straps. If you want the t-hooks to keep from marring the frame, dip them in plasti-coat or use some old strap material to minimize the contact.
Growing up on the farm, you learn that you strap it tight so that nothing moves. I know that some let the suspension move, but I look at that as energy that is uncontrolled when you go over some bad bumps (and may have to do emergency braking on top of that). I have never had an issue with the car going anywhere when locked down tight!!