Looks like I was overthinking the whole spinnaker halyard rigging issue.
I have a snap hook on the end of the halyard and to to get it to the other side of the jib/stay I just throw the halyard out past the bow in a kind of arc where it comes back to me on the other side of the stay.
My setup is to have snap hooks on the halyard, clew sheet and both ends of the tack outhaul which runs through a block on the bowsprit. This allows the tack to be hauled to either side of the bowsprit. Once the sail is doused I remove all 3 snap hooks, throw the halyard around the stay and reconnect the 3 lines to the sail on the opposite side.
Today, with the boat on the trailer and while standing in the companionway I raised and doused the sail 4 times and it all worked well although It will take a bit more practice to be able to do all of this quickly and confidently.
Thinking it's also time to construct a tiller extension to be able to make steering adjustments while tussling with all those lines