I am doing a 52" swap on my 71 blazer this weekend using 89 van springs. They line up really well, with the center pin lined up the front spring eye is only about 1.5 inches forward of stock, but I want the axle 2 inches forward so I will put the new hangars about 3.5 inches farward. It puts the shackles just about in the perfect spot. I have furd shock towers ready to go in, and will do the crossover if needed but probably when it's done. I'll try to take pics as I go since first gen swaps don't seem very common! One thing I am worried about is making sure my measurements are spot on so it doesn't crabwalk. WHat have you guys done to ensure everything is square?