As promised, here are some pictures. I looked at the car closely and thought through what would happen if the car would be towed from this point. Specifically I had to think through where the force was going to be applied and what other components could be affected. No use in having a tow loop that if you use it your valance, bumper, etc are going to be damaged in the process. So, I decided that the best place for the tow point to be located would be directly in the center where the license plate would reside. Here is WA because of the age of the car, we can get a "collector" plate which only has to be displayed in the rear, this leaves the front open. However I intend to still have the capability to put a front plate "just in case".
I decided to put a solid bar running between the 2 inner bumper brackets. I used a piece of 1 1/8" square stock, drilled holes on the end and tapped them 1/2 x 13 and installed the bar using grade 8 1/2" bolts. Another design consideration is that it had to be removable, so this was the best method.
At this point I have a solid mounting point, what I am struggling with is the tow point design. If I make the loop so that it faces horizontally (like most you see on race cars); I have to lower the tow point itself to all room for a tow strap; so that under load the strap isn't pushed against the bumper (would probably remove the paint or at a minimum damage it). I am leaning towards making it sit vertically which solves the other problem but I don't think it will be all that good looking. So, now I am thinking vertical is the way to go but it needs to be removable (similar in concept to a receiver hitch on a truck).
I am going to work on this today so we will see what I come up with.