question regarding block rendering

Hi there, I'm currently making a PBR texture for gregtechModern, now I have an issue with the gt blocks. As you can see and guess from the images, for some machines in gt, they are the combination of 1 layer of base texture and a machine texture (ie. base firebox texture + fire effect texture), Referring to image 1 and 2, if I don't add them to the light source list of ray tracing shader, then they are not considered to be light source and will not glow. While referring to image 3 and 4, if I add the machines blocks in any category of light source in the block.properties of ray tracing shader, whole the block instead of only the fire effect glows. Is there a method for ray tracing shader to only read the emissive texture of the cover layer (ie. fire effect , green box in image 1, computer overlay in image 4) without adding the machine blocks to the block properties? thanks