Dash Lights
 

I was reading the sticky, all I have to do is take the plastic blue/green inserts out? I would like to use a red LED.

Yes that is it

Remove diffusers in order to do what, replace the bulbs? Yes.

I prefer to pull the entire cluster assembly out and pull the twist-lock sockets out from the back.

I think he wants to install Red LED's in his insturment cluster.

Red wavelength through a blue/ green filter would not pass much light.

Remember when you could reach under your dash and replace the light bulbs without having your head under the brake pedal?
1960 Chevy Apache 30, even the 1972 C-30's

Jim