Here is a good side profile of the car to see how much of the frame rail hangs below the rocker. (The body was still slightly sitting on the trans so the front is up about 1/4" higher than it should be)
Here is a shot of another 66 that we are just starting on. This is on the stock frame with original 1966 bushings. The frame rail is right at 1.75" from the bottom of the rocker pinch weld.
And here is a pic of our low profile frame rail with a ruler clamped to the bottom of the frame rail. It is right at 1/2" below the rocker pinch weld! That is 3/4" higher than the stock frame rail. (stock height Energy Suspension body mounts are installed)