Squarring the Rear-End after Spring Install?

Most are never square from the factory. That is why guys have to hold them straight doing a burnout, X the rear by measuring from the rear of the front frame to the locating pin on the spring. Shim the short side back by adding the correct made spacer to the front of the front spring hanger. There are some cases where the studs have to be made longer, . Fine adjustments may have to be made to make the car launch straight. The most I have seen that had to be added over the years is 1/2 inch. Always do this before installing a inboard kit. Once you weld the boxes in you are committed to the location you chose. In this case measure three times weld once.