trbenning,through the rear cross bar???
On my 21SE the trapeze shock cord runs behind the wing seat and through a grommet on the tramp.When I added my third trapeze wire,I also had to add a third grommet on my tramp for it to pass through.I can't remember if that third grommet was punched about a foot behind the other two grommets or a foot forward of those existing grommets.
I have two hi-low adjustable trapezes and a third non adjustable trapeze wire per side and the adjustable ones are so much easier to use and get nearly all the use.I have always wanted to replace that non adjustable trapeze with the hi-low system,just have not spent that money yet.I have had three people trapped out and me sitting aft on the wing with the hot stick and main sheet, holding my cat from flipping many times in high wind.
Think white caps with little whirlwinds of mist flying everywhere......
Bill 404 21SE