Todd,
Go to:
http://user.tninet.se/~zdt420t/index.htm - click on both the M20 and M18 pages there are good pictures and exlpinations of the Marstrom spinnaker retrival system. The best imformation is on the M18 page. It looks very good.
On the M20 boats the pole is held in place by 2 carbon rods (they are in the pictures). Somebody helping move the boat before the Texel use one of them as a handle. It broke and the M20 never got off the beach :-(