Sadly, my Pearson 33 does not have a spinnaker halyard so I'm out of luck, but you should head over to the UK Halsey wesite and look at their video. They call their assymetric a "Flasher"
Definitely the dousing sock is the way to go.
No need for a sprit.
1971 Pearson 33 (for sale!)
1992 Hunter Legend 35.5