I hope it is not the elevator itself, as I already had to cut the old one off because of a warp. The cut CA hinges from that removal are still enbedded in the stab trailing edge, so if I have to remove the elevator again I will have no new area to cut new hinge slots.

The control horn is at a slight angle as per instructions, but maybe I should have had it straighter anyway. But I don't believe the horn has anything to do with it because the buzz is still there even with the horn end disconnected. The pushrod opening is clear and the rod slides cleanly in and out of there, so it looks like that leaves the rear-end OK. The servo end is not hitting or rubbing anywhere and the arm is moving freely. That leaves inside the fuselage, but looking inside I still don't see anything rubbing or binding. Please don't tell me I have to rip the covering off to investigate further.