Gennaker Rigging 1992 One Design

Hi to all. I’ve been refurbishing a 1992 One Design and have run into a snag with the gennaker rigging. I read previous posts, but my boat was fully dissembled and I’m missing a few parts  .  I see from previous posts that the gennaker halyard runs through a floating block at the base of mast and that is attached to the bowsprit pole launching line.  My boat is missing this line.  I have a shock cord coming from the back of the bowsprit and is tied to the transom in the cockpit.  There are also pulleys in the back of the bowsprit I’m not sure what they are for. Where does the launching line come from?    Also,  the gennaker retrieval line..is that just an extension of the halyard that passes through the genn sock and up to the retrieval points on the sail?  Thanks in advance for any info!