CUSTOM METAHUMAN IRIS TEXTURE

Hi, does anyone know how to use custom iris textures for the new metahuman eye shader?
I tried replacing the iris MF with a custom iris texture sample, but resulted in sharply displaced iris.

Orig Iris MF
Imgur

Replaced with Custom Tex Sample
Imgur

Does anyone know how to change the iris wo breaking the shader? Thanks!

Did you find a solution to this