That is looking very nice; great work so far. I would like the end result to be monotone I think.Of course, anything that is not "engine" should be black.When you put these textures inside a cowling, the outside edges are typically shadowed (as they are up in the cowl) and the overall texture is dark. as it gets little sunlight. The main objective for me would be "make it subtle", not jumping out of the engine cowl. Great work!Not perfect yet. But would like opinion if it's usable.
EDIT: Here are two examples I used for the A26B that shows my preference. Of course, as the artist, you have the license.