[Bill Rose]

I agree, don't use an impact wrench. I just did this a few weeks ago on my 69 ElCamino. I used a 2 foot long breaker bar on the spring compressor, and used long smooth strokes. It is a little scary, but it has to be done. The spring has to be compressed to 13 inches long in order to install it in a 69. I would imagine 67 is the same. If it's compressed to 13 inches, you can stick it up into the frame and raise the lower control arm, and get the nut on the lower ball joint, without scratching anything.