That seems cheap enough if it was factory.Did it also include the drill and tap?D*
Since there are no stainless D-frames, someone was probably trying to match a nickel finish. I doubt that bare aluminum matched the "yellow" cast of the nickel finish very well.Judge, that's what I think happened. The finish was removed to be used on a stainless revolver.
I have an unfired 1966 Cobra with the shroud installed at the factory. Do you know the details of how Colt installed/drilled them? (I'm not going to risk buggering the screws on mine to find out)The backstrap screw was easily drilled and tapped as we could angle the vise on the drill press table to the proper point.
The two on the side of the frame couldd either be done with blind bottom, or drilled through.