I have a 95 Ranger STX, 4.0L, 4x4, extended cab. I would like to know which coil springs to use to replace the worn sagging springs that are on it now. I have a 3 digit spring code on the door label so I'm not sure what springs are suppose to be on it, since they are typically 2 digit codes. I'd prefer the strongest stock coil springs because I'm planning on dropping a 5.0L engine in it in the near future, but I have no idea how to tell how strong the springs are. I have a Ford service manual for the Ranger, but it is little help.