Take a good light under the car with you and have a look at the housing. Pay particular attention to the lines formed in the housing axle tubes. If I am not mistaken the axle housing is rolled from flat sheet and it will have die form lines, scratched into it. The tubes also are welded into a round shape so, you may be able to find the weld line. If they are straight, the housing is golden. Helped a racer once that had changed the spring perches 2 weeks consecutive because, I kept loosing pinion angle. We got under the car and found the housing a mess.
