After hearing so many positives about having a rear wind restrictor, I found this relatively cheap one on ebay to give a try:
https://www.ebay.com/itm/254657288487#rpdCntId
It came in today, I installed it, Justina, Athene and I hit the road and within a couple of miles I pulled over and moved the 9" Madstad windshield from being fully down to fully up. This helped a minor amount but after a few more miles I pulled over again and just removed the restrictor and stuffed it behind the seat. It was creating more turbulence than without and I suspect that it is not compatible with the windshield. Yea, I am kinda disappointed!
Bill