here is there email reply.
The number on the end of the springs is the last three digits of your order number. This is how we signify which spring is for which order. To install the springs, Bolt the spring to the front hanger and then bolt the hanger to the frame. Then bolt the spring to the axle. This way you can use a jack to push on the axle to put weight pressure on the spring so that it will reach the rear shackle area. Many times you cannot just put a spring up in place and bolt it in...the arch makes it necessary to compress the spring some to install it. This will essentially lengthen the spring if you are measuring straight across. If you have any other questions, please feel free to email again. I've checked the specs on the springs and they are correct for your car.