Hello,
Take a look at the conversion video shown below that works for Simonton windows that use this type of assembly. Note that the shoe, coil springs and pivot shoes will need to be replaced with the parts featured in the video. Take a look and review the full process below. Thanks for posting!
We are not able to process orders through this thread but they can be purchased directly on our website or by giving our customer service team a call at (888) 991-1929. Keep in mind that you will also need S159 coil springs that work with the 15-259 pivot shoe as shown in the conversion video. To determine the strength options, you'll need to weigh the window sash and divide the weight by two if you plan on using one coil on each side. You are correct that these parts would be used on both sides of the window.