Drilled holes into the inside-face of the hinged assembly, big enough to get the screw-head in, the opposite face has a thread-size hole. Stuck a sharpie through the holes to mark the small hole onto the frame-assembly. I tried using a transfer-pinch but it couldn't get a positive fit into either the near or far hole. So I just eyeballed it and hand-punched about in the center of each sharpie-circles.
Screws fit nicely, and give me access to tighten them down.
Now for the not-so-fun part, again, trying to drill Chinese-bead-frame a.k.a. adamantium. Regular drill-bit made a small dimple before it started squealing badly. Switched to a brazed-carbide masonary bit that I ground with a vintage craftsman drill-sharpening jig.
Lots and lots of pressure (all my weight basically) and trying to keep the drill just barely faster than the bit-stall speed. Made it through five-of-six holes. The left-most dimple simply refused to be converted into a hole. Re-sharpened my bits twice, still no love. Must be hardened-adamantium.
Made a half-arse attempt to temper the adamantium back a bit using an oxy-propane torch. Heated the whole thing up until it got dark-blue.
Then I played the flame around on it for about 5 minutes so it would cool off a slowly as possible.
Still no love! Masonry bit just got super hot, and I started to worry about loosing the braze and/or temper of it's shaft. In a last-ditch effort, switched to the tear-drop masonry bit + hammer-mode and what-ya know? It blasted right through!
The bit didn't fare well, giant chip of carbide fell off the back of the right-side flute. No matter, though, it's a cheap bit and I have the final hole.
Now, I used the movable-jaw of a bar-clamp to steady a length of angle-iron (store-bought, non-Chinesium, lesson-learned). The band saw slices and dices...in the grand-tradition of cut three-times, sorta-kinda-measure, and prey it will all work out in the end.
Used cutoff-wheel in my grinder to cope the ends of the angle-iron. Then some TIG tack-welding happened.
Damn, should have preyed harder, it doesn't fit at all. Though you can kinda see what I'm goin' for here. Okay, onto the final step...
...Draw up some plans for the second-try, get a new piece of angle marked and build the same thing again, only with correct dimentions this time