We did this on a 2144. I believe it was a Crary chaff spreader. To make it so the straw didn't hit the chaff spreader we put two spinners on off an xx88 but remove all the bats. Then we put on two of the old,old style bats turned backwards so the lay across the spinner plate and up the cone. This will keep the straw moving through and lift it out and over the chaff spreader. Sometimes it does leave the windrow a little bit ragged and so we would take one bat off each spinner and just run with one. If the spinner plates aren't almost touching on the 1688 you will need to make new ones that do. If there is much space between them straw will get down through it onto the chaff spreader. Make sure someone is watching when you first run with this setup to make sure the straw is feeding through and doesn't plug up. We never had that problem but an 88 will feed more straw through than a 44 so I'm not sure how that will effect things. I always kept an eye in the mirror to make sure I had a windrow behind me.