Well I didn't have anyone around to help, and so I put the brain to work.  Changed out the bungees on the Kitfox 1.  Dave the Kitfox flyer from Canada has a video of him changing the bungees and using a hammer handle to hold the bungees between wraps.  He had a helper though, I didn't.  I wedged a board between the hammer handle and the seat to hold the top bungee wrap, but wasn't able to pull the bungees tight enough to get the right number of wraps working just from the top.  I cut a board off that was long enough to wedge between the floor and the landing gear to lock the bottom bungee wrap while I climbed up and pulled on the bungee in the cockpit.  Used vice grips to hold the tail end of the bungee while I tied the loop in the end.  I don't think I could have done it if both loops were made already, it would be real hard to pull on the last wrap of bungee with nothing much to hold onto.  I had about 2' extra of bungee so had a good handhold and that also made it easy to clamp off with the vice grips.  Anyway, it worked.  It would require something that you could hook on an Avid seat truss to make this work on an Avid.  Kitfox's seat truss is built different and has a place for the hammer handle to go.  Anyway, I'm proud of myself, even if I've had to take an hour's rest after I was done.  ;-)  Jim Chuk