Well, here are the photos:
Side view. The reflector glass is in 45 degree angle.
Another view
Looking through the gunsight.
Looking through, from longer distance
This is what it looks like from top of the gunsight. It shows the reticle through the glass and inverted reflection.
For the simpit i'll naturally remove the cover. This way the gunsight looks just like any WW2 fighter's gunsight. At least il2 supports removing any on-screen sights so maybe i'll even get to play some games with hardware gunsight. Otherwise it'll just look cool :-)
Btw notice how the size of reticle is always the same regardless of the distance. That's how the reflection gunsight (and modern HUDs) are supposed to work.
Next step is to mount the thing to the simpit. Let's see when that happens, as i have some other projects (hacks) to do such as the RC 109 used as practice target in photos above.