I think we've all managed to drop the pin in the sand, or onto a hard surface where it bounces off into another dimension
I'm not sure how best to explain it, but since the halyard pulley is higher than the forestay hound, I tie the halyard thru the shroud extender and shackle, so that the rope and knot are above the pin holes. This points the shroud extender down a bit, and lines things up better for pinning.
The other thing to remember, the rig doesn't need to be very tight. Not like a typical monohull. So just pin it where it's easy to insert. Folks who race Waves always keep the rig really loose and sloppy. For recreational sailing, it gets a little noisy if you get into powerboat chop and the mast starts flopping around; but I'll just grab a shroud and pull it tight until the chop subsides.