I don't think it is possible to have a 3D VC HUD in the default FS Bell 206 helicopter because it doesn't have one first place. So you can only add the 2D HUD. To add Weapon for FSX to the default Bell 206, just run the "Loader", select "Rotorcraft", select the Bell 206, click on INSTALL.

The panel.cfg will add the 3 windows to the panel (see attached image):

[Window Titles]
Window00=Main Panel
Window01=Weapon Control Panel
Window02=HUD
Window03=HUD Glass
Window04=Compass
Window05=Mini Panel
Window06=Radio Stack
Window07=GPS
Window08=Collective

You then use SHIFT+2 to open the Weapon Control Panel, SIFT+3 to open the 2D HUD and SHIFT+4 to open the HUD Glass.

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