Ok, I have to retract my info, as a member on PY has enlightened me with his experience and knowledge of these fiber optics for the Mid body styles like the GTO/ Lemans and small body style Firebird. (Thank you Guppypuppy2!!) Just when a guy thinks his research is complete... Apoogies for the miss..

He has provided the pictures as well below:

So it turns out that the fiber optics like I purchased are indeed for big body cars only with multiple applications. (Hence the light bulb housing)

For the smaller cars, the fiber optic cable for the ignition or ash tray is basically mounted to a bulb in the back of the instrument cluster on a special bracket.

For the ignition, the cable is secured to the ring that fits around the switch, and the fiberoptic actually sits in a hole in the side of the switch. The light then shines into the cylinder and illuminates the key hole itself.

The ashtray fiberoptic mounts to the back of the cluster as well, and mounts to the tray slide.

He also mentioned that the 67's were different- they did use a bulb for illumination, with the same style of ring as a mount for it.

I want to put this info here as well as PY for anyone who needs it in the future.