I guess this is waiting for a problem type of project but you must admit it looks nice. I needed 12 segments in addition to the end pieces to finish my chain. I don't know about the variance of cable length so YMMV of course.Assemble the complete chain before mounting it in the machine. The tolerances are tight but I made the pieces quite rigid to keep them from flexing. Once the chain is mounted it starts getting tricky adding bits due to lack of space.The angled piece replaces the first little black clip that secures the cable into the bed, just unscrew it and replace with this thing.To fasten the bottom end piece I used double sided tape since I didn't need to drill any holes in the machine. Make certain you angle it so that the chain doesn't curve under the bed. I suggest that you manually move the mattress up and down a few times to make sure everything clears before letting the machine do its thing on its own (do not ask me how I know, let's just say this wasn't the first layout...).