I finally came up with a workable idea for mounting the antenna. I made the antenna from hard balsa using BT's outline. then I inserted/glued some 4-40 rod into it. I already had made a reinforced slot under the covering on the fuse spine. I then fashioned a retention mechanism using a small wheel collar with a 4-40 bolt and a block of balsa. The antenna goes into the fuse, through the wheel collar, and then I tighten it down through the access hatch.