For the smaller jib I would need to add two blocks to the front crossbar. Perhaps I could use the existing jib blocks for a spinnaker.

How does a spinnaker pole attach to the boat? Is it easily removable, and do you take it off for trailering? How do they hold up if you pitchpole? It looks like you need to add an additional mast tang, too. Are there spinnaker kits available?