Does something like this work for you .... I think I had read GWS were trying to grab a first rounder out of you to go with Shaw to give up Adams.. Basically is an 8 pick slide back down the order (5 pick slide really as Norths pick is committed, one of the picks is committed, and it sounds like you and West Coast may already know who they intend to pick at 11)
Port: 14 -> GWS for 21 + 22
GWS: 14 + Adams -> Collingwood for Shaw and 6
Port: 22 -> Brisbane for Polec