I would put the stab in position and mark the outline of the fuselage on the stab (both sides, top and bottom). Remove the stab and use a sharp exacto knife to remove the covering on the stab just inside of the fuselage outline so that you will have good wood-to-wood contact where you are going to glue the stab (careful not to score the wood with the knife, thereby weakening it). Using 30-minute epoxy (or longer), lightly coat the wood in the contact areas of the stab and fuse and allow it to soak in for a couple of minutes. Then slide the stab into the fuse, stopping just short of fully inserted. Add some more epoxy to the still exposed side of the stab, push the stab through and expose the other side and likewise add more epoxy and then properly center the stab. You can use paper towels and alcohol to remove any epoxy that got onto the fuse or stab covering.