The stock coil spring pockets must be trimmed to fit the larger diameter of the air springs. Air Ride Technologies' Rodney Mason used a pneumatic cutoff wheel to get the job done. Does the trimming weaken the area? Rod says, "No way. There are so many overlapping bits of metal here, it makes no impact on strength." Just be sure to make curved cuts and avoid hard 90-degree intersections between cuts that could form stress risers.