Replacing Longitudinals, frame alignment? Options

[riverman]

I'm in the process of repairing the longitudinals (inner and outer on both sides) and I am concerned with keeping the frame aligned while do this. There is no point in fixing up one of the best handling cars in the world if it won't track straight when I'm done.

I have placed jack stands under the front suspension and under the firewall with a 2x4 runnning between the jacks. At the rear trunk cross member I have two adjustable jacks that I can use to raise and lower the rear to keep door gaps looking good. Once I got the door gaps adjusted I set some other pieces of wood between the windsheild frame and rollbar and strapped them in to keep the roof opening measurement correct. I'm considering putting adjustable jacks at the front corners too so that I can adjust each corner of the car seperately. Now I'm in the process of repairing the longitudinals and getting ready to install a frame stiffening kit I ordered from Brad Mayeur. The car sagged when I got it and I want to be assured that it it is straight and strong when I get it on the road.

If my doors open and close smoothly, is my car aligned properly? Could the car still be twisted between the front and rear wheels? If my exterior measurements are correct, then the frame has to be aligned, right? How much tolerance would there be in the dimensions from a car that came from the factory? Is there anything I'm missing, or ot thinking about?