Figures...realized today that I've left the camera in a bag at work.
Have come up with a bit of engineering that should be quite stable, however. Strengthened the 'floor" that the fin glues to, then keyed the fin into the TE of the stab. Fuse sides were then given a bit of extra material to make the saddle's roughly 5/8" wide where the stab sits. Finally, rather than the ABS "fairing" that was supposed to go over the top of the stab...which didn't lock the stab in OR look right anyway...some sheeting will be layered in, and sanded to the right contour, which should both look better AND lock things in nicely.
Things are moving along nicely. Tail feathers are all covered, surfaces hinged. Fin and stab are mounted (stab is curing s I type), and the bottom of the fuse, as well as the underlying red layer of the sides, are covered. Servo extensions and rudder cables are run as well, and the lines have been struck for the motor box/firewall to get the DL mounted up.
Given a bit of luck the next day or so, and with the holiday weekend, MIGHT just get this bird in the air Monday.