[bret a ewing]

Just got off the phone with Shelby's suspension guy, Tom Bernard. Seems the early a-arms (around CSX 4802) were longer than are currently in use, which is the exact reason I am having a problem with achieving proper camber. You can recognize the new from the old by the distance of a-arm tube after the weld, this is the threaded part the heim joint/turnbuckle adjustment screws into.
In other words, if the threaded part of the arm is flush with the weld then it is the newer design, if there is .75" to 1.5" after the weld it is the old design and you probably dont have spec caster. To correct you must cut your a-arms, I'll let you know how it turns out..............