Yup Xist, that's pretty much what I have, except the tail surfaces are curved instead of straight.
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I mocked up a CAD* fender skirt and did another quick tuft test.
It seemed to do the trick!
Aside from the area of deepest curvature in the transition from skirt-to-tail (green circle), there's now little or no recirculation in the tufts compared to before. Plenty of turbulence, oh yes, but the airflow is now going the right direction:
(* Cardboard Aided Design)