Replacing Instrument Cluster bulbs with LEDs - Illumination Detail Question - 67 Barracuda

I am going to use gauge face overlaps in white when I replace the dash bezel; as well as upgrade to LEDs.
I have used LEDs in the past to get better Illumunation. But, I have not disassembled the 67 Barracuda dash yet.

The gauge face overlay folks I am considering say to simply use their overlays over top of the OEM faces! i.e., you don't have to remove the OEM faces!
But, if the gauge face lighting is coming from behind the faces, that would be cutting down on the transmitted light.

So, my question is....with the 67 Barracuda gauge faces, is the light coming from the periphery of the gauges (from the sides); or from behind?

This relates to some of the past posts on this Forum about whether the LEDs should have diodes all facing forward; or some diodes on the sides of the LED, scattering the light.
I did the white overlay on the stock face and LED’s. 71Duster Came out great

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