Hey.
I understand exactly what you are saying. what i said is even the top picture. i.e. pre 2008,, the gunslght still floated off the HUD. and if you played the game back in the time, the gunsight also floated out on left/right/top side of the HUD, depending on what your roll position is.
If you check my "better CCIP" mod back 10 years ago. I already RESTORED the gunsight to the state in the top picture for SF2.
But that is not a real fix, especially for CCIP. Because if you roll your flight left or right, CCIP will be at the transparent part of the cockpit where no dashboard available to block the reticle. you will see ccip off the HUD on the left or right hand side of glass.
What I resolved now, is that the entire HUD will stay in the HUD glass. if it goes out, it gets clipped and you won't see the part fall outside. And i have made the gunsight/CCIP such as well.
The fundamental reason behind the issue of floating gunsight/CCIP, is because TW didn't code them as HUD object. They are actually handled as a flighobject that through a standalone shader they mix with the hud object at the end of graphics pipeline.
As such no matter what you do with HUD, you can't fix the gunsight/CCIP, because they are not even a HUD object.
What I do now, is completely disable the stock gunsight/CCIP draw. And draw a new gunsight/CCIP as a part of HUD. I can then influence, clip or cull the HUD and achieve consistent result between HUD and gunsight/CCIP.