Heres how we solved the lock problem. At Lowes we bought a standard Desk draw lock with a 1 inch shaft. We then drilled out a shaft diameter hole in the side of the fuse below the ¾” Angle making up the upper edge. See the lock after mounting on the outside of the fuse.
Then we cut a channel in the top surface of the edge for the arm of the lock to come up through.
We then put a small length of ¾” angle on the inside lower edge of the f the canopy frame.
Then we cut a slot in the arm of the lock to capture the piece of angle.
That’s it. Caution I would not buy the lock from Aircraft Lowes. It had too much play in it. But we made do with what we had.