What is the difference in the front suspension (spindles/springs/control arms) and brakes/rotors on theses three models?

I have an 03 5.4L V8 Supercrew and am wondering if the Harley & Lightning set ups are the same? Did they use the same springs? Do they have different upper or lower control arms than the standard Supercrew?

Did the 03 Supercrew get bigger brakes than reg cab? Are the Harley / Lightning brake identical? Is it worth the $$ to change from Screw to Harley/Lightning brakes or just go aftermarket??

How does the NASCAR edition factor in to the equation?

Lastly has anyone used the new 2" drop spindles for the 99-03 F150s yet?

Thanks!

 

The only suspension difference I know of on the Harley and Lightnings are one inch lowering springs (front and rear). I believe the brakes are the same.