need 2x 0.7x7.5x30mm springs. 0.7mm wire thickness, 7.5mm OD, 30mm length. I got it from amazon B0BL7RYQ27

need to take the seat off first. you can use the Herman miller pdf for "sayl disassembly for recycling" for reference as well as the video from YouTube https://www.youtube.com/watch?v=yP1YdK3gNhw

you will also need to take off the bottom plastic trim. besides the 4 screws you need to undo 4 clips. I have included the pics. The teeth part of the metal clip latch on to the plastic tabs on the trim. the metal tongue sticking out near the u-bend is latching into the plastic slot on the bottom plastic seat body.

after you're done need to cut 2 ends of the clear part so the 2 ends doesn't stop the seat from moving. I just used a box cutter