So since the repairs, and the fixes of the underbody stuff on my car, I've tried to keep driving habits in check to see what the changes would be. Even with a few (rather needed) WOT freeway entries, and wet road hoonage the last few days thanks to Hurricane Dolly, So far the car has average an estimated 18-20 mpg over the last half-tank!
Compared to the last tank where it barely managed 11 mpg, that's a huge improvement for me!
For the most part, I Neutral coasted off the highways, and engine braked when ever it was good, and other then that a bit slow on the freeway helped a lot. Since I live just off a highway (only way to get anywhere), I figure doing 60-65 instead of 70+ made a big difference.
So, thanks for the bit of help and all the good reading here. Saving my butt some green.