[bobss396]

I've changed a few of these on the old Impalas and never gave that hole any consideration. I believe that it is a tooling hole for the frame fabrication.

The lower end of the spring orients itself on the lower control arm nicely. What is the top of the spring like? I think they had the fully formed coil, which might also locate up in the spring pocket. With the spring out look up and feel the inside of the frame pocket to see if there is a stop of some sort in it.

It might have a hub that the spring has to go over squarely. Use a spring compressor that fits inside the spring itself, watch carefully to make sure that the spring is square in the upper pocket, it will be obviously biased to one side if you miss the locating hub. But the spring is easy to jockey around using a big screwdriver or prybar. You'll have to loosen the compressor a little at a time until the spring seats at the top and you can attach the lower ball joint.

Bob