No info found. I can't remove unless I cut open grove

Thanks for reaching out to us. Your coil spring pivot assembly is the earlier model that has been replaced with the 15-087 pivot shoe and S180 coil springs. To remove the old balance assembly for the bottom sash, pull out the track cover and you should see a cut-out at the top of the track. If not see the video below on how to make a cutout in the window track. 

You will also need to weigh the window sash and divide it by the total number of springs in the window to determine the proper spring weights. 

Let us know if you have any questions!