This is 150 pound test braided fishing line. it is thin, tough and will not stretch. perfect for this job.   Each end is tied into a loop. the first loop is slipped over one hook end.  

  Bring the line around the boot. Yes, the boot that should be here, but isn't.   Continue threading the line around the drum, alongside the cable.  

  Bring the other end through the second spring hook, and pull back.   I used a nutdriver through the loop at the end of the line as a handle to pull the line to stretch the spring.  

  Here's a shot of the spring and cable disconnected.   Reattaching the cable to the spring  
  For info, in the two shots above, I am holding the front of the drum upright between my knees, holding the camera with my right hand, and stretching the spring out with my left.  

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