[57hemicuda]

Scott,
I find it easier to pull a chalk line front to back down both sides just below the pinch welds (If you are going to be a while, use tape). Along the whole length of the car, making sure they are parallel with one another. Then two in the opposite direction somewhere near the wheel mounting surfaces. Making sure to X them out to be sure they are square.

Once you have made this perfectly square box, and the car is solidly mounted and level, pinch welds in perfect line with your tape. All you need is 4 plumb bobs, a tape measure, digital level, and a patient wife or buddy to hold the other side of the tape.

You can accurately measure wheelbase (or altered wheelbase in so many cases), track squareness, camber, caster, pretty much anything you would need to know.